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| Intellectual disability syndromic and non-syndromic v1.59 | HECTD1 |
Chirag Patel gene: HECTD1 was added gene: HECTD1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: HECTD1 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: HECTD1 were set to PMID: 39879987 Phenotypes for gene: HECTD1 were set to Neurodevelopmental disorder MONDO:0700092 Review for gene: HECTD1 was set to GREEN Added comment: 14 unrelated individuals (identified through GeneMatcher) with 15 variants of uncertain significance (VUS) in HECTD1 (10 missense, 3 frameshift, 1 nonsense, and 1 splicing variant). Of the 15 different variants in HECTD1, 10 occurred de novo, 3 had unknown inheritance, and 2 were compound heterozygous. All variants were absent in gnomAD, and HECTD1 is highly intolerant to loss-of-function variation (loss-of-function-intolerant score of 1). Clinical presentation was variable developmental delay, intellectual disability, autism spectrum disorder, ADHD, and epilepsy. The one individual with compound heterozygous variants had growth impairment along with NDD. The variants were inherited from apparently healthy parents, suggesting that genetic or environmental modifiers may be required to develop the phenotype. Significant enrichment of de novo variants in HECTD1 was also shown in an independent cohort of 53,305 published trios with NDDs or congenital heart disease. HECT-domain-containing protein 1 (HECTD1) mediates developmental pathways, including cell signalling, gene expression, and embryogenesis. Conditional knockout of Hectd1 in the neural lineage in mice resulted in microcephaly, severe hippocampal malformations, and complete agenesis of the corpus callosum, supporting a role for Hectd1 in embryonic brain development. Functional studies of 2 missense variants and 1 nonsense variant in C. elegans revealed dominant effects, including either change-of-function or loss-of-function/haploinsufficient mechanisms. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v1.37 | EEFSEC |
Zornitza Stark gene: EEFSEC was added gene: EEFSEC was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: EEFSEC was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: EEFSEC were set to 39753114 Phenotypes for gene: EEFSEC were set to Neurodevelopmental disorder, MONDO:0700092, EEFSEC-related Review for gene: EEFSEC was set to GREEN Added comment: Nine individuals from 8 unrelated families reported with bi-allelic variants in this gene and progressive neurodevelopmental disorder manifesting with global developmental delay, progressive spasticity, ataxia, and seizures. Cerebral MRI primarily demonstrated a cerebellar pathology, including hypoplasia and progressive atrophy. In line with the clinical phenotype, an eEFSec-RNAi Drosophila model displays progressive impairment of motor function, which is reflected in the synaptic defects in this model organisms. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v1.30 | UBR5 |
Bryony Thompson gene: UBR5 was added gene: UBR5 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: UBR5 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: UBR5 were set to 39721588 Phenotypes for gene: UBR5 were set to Neurodevelopmental disorder MONDO:0700092, UBR5-related Review for gene: UBR5 was set to GREEN Added comment: 29 individuals with a neurodevelopment syndrome (24 de novo variants) with a core phenotype characterised by developmental delay (26/28), autism (16/26), and intellectual disability (56%). Additionally, some individuals presented with epilepsy/seizures (11/27), movement disorders, and/or genital anomalies (35%). Loss of function is the expected mechanism of disease with functional experiments in C. elegans and in vitro ubiquitination assays. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v1.10 | MGA |
Zornitza Stark gene: MGA was added gene: MGA was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: MGA was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: MGA were set to 39600096; 20044811 Phenotypes for gene: MGA were set to Syndromic disease, MONDO:0002254, MGA-related Review for gene: MGA was set to GREEN Added comment: Three individuals with de novo LoF variants reported in individuals with ID and congenital anomalies. Zebrafish model supports role of this transcription factor in organogenesis. Note there are previous, less clear reports of association with NDD/CHD. Gene is constrained for LoF variants in gnomad v4; however, note there are ~30 individuals with LoF variants present. Borderline Green/Amber. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.6628 | MARK2 |
Chirag Patel gene: MARK2 was added gene: MARK2 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: MARK2 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: MARK2 were set to PMID: 39419027, 39436150 Phenotypes for gene: MARK2 were set to Neurodevelopmental disorder MONDO:0700092 Review for gene: MARK2 was set to GREEN Added comment: 31 individuals with autism spectrum disorder (30/31), intellectual disability/developmental delay (100%), motor delay (62%), speech-language problems (100%), seizure/epilepsy (46%), behaviour disorders (ADHD, aggression, anxiety)(74%), and distinctive facial features (narrow face, abnormal or broad forehead, downslanting palpebral fissures, and large or dysplastic ears). WES/WGS identified 25 LOF and 6 missense variants in MARK2 gene (Microtubule affinity-regulating kinase 2) which contributes to establishing neuronal polarity and developing dendritic spines. LOF variants were de novo (16/25), inherited (4/25), or unk (5/25). All 6 missense variants were de novo and clustered in the kinase or KA1 domains. The mRNA and protein expression of MARK2 in PBMCs were significantly lower in affected individuals with LOF variants than in the control group. In vitro expression assay of missense variants supported the effect of MARK2 loss. Proband-derived and CRISPR-engineered isogenic induced pluripotent stem cells (iPSCs) showed MARK2 loss leads to early neuronal developmental and functional deficits, including anomalous polarity and disorganization in neural rosettes, as well as imbalanced proliferation and differentiation in neural progenitor cells (NPCs). Mark2+/- mice showed abnormal cortical formation and partition and ASD-like behaviour. Through the use of RNA sequencing (RNA-seq) and lithium treatment, they linked MARK2 loss to downregulation of the WNT/β-catenin signaling pathway and identified lithium as a potential drug for treating MARK2-associated ASD. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.6604 | ANKRD31 |
Megan Ball gene: ANKRD31 was added gene: ANKRD31 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: ANKRD31 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: ANKRD31 were set to 27541642 Review for gene: ANKRD31 was set to RED Added comment: 1 individual with Rett-like phenotype. De novo missense. C.196A>T, p.Ile66Phe. Onset of features at 3 years, delayed ambulation, epilepsy, developmental regression, stereotypies, non-verbal. 17 years old at time of publication. A C.elegans model of ANKRD31 with a deletion showed significantly defective locomotion and asymmetric dynamics of axonal and dendritic microtubule defects. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.6548 | DHRSX |
Zornitza Stark gene: DHRSX was added gene: DHRSX was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: DHRSX was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: DHRSX were set to 38821050 Phenotypes for gene: DHRSX were set to congenital disorder of glycosylation, MONDO:0015286, DHRSX-related Added comment: PMID:38821050 reported the identification of biallelic missense variants in DHRSX gene in four patients from three unrelated families with a congenital disorder of glycosylation. They displayed distinct facial features, severe neurological involvement including hypotonia, scoliosis, contractures, profound intellectual disability, epilepsy, and sensorineural hearing loss. These patients also experienced severe failure to thrive (requiring tube feeding); variable respiratory insufficiency; and involvement of the eyes, the gastrointestinal system, and other organs. Gene located in PAR. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.6513 | GLB1 | Bryony Thompson Phenotypes for gene: GLB1 were changed from to GM1 gangliosidosis MONDO:0018149; mucopolysaccharidosis type 4B MONDO:0009660 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.6510 | GLB1 | Bryony Thompson reviewed gene: GLB1: Rating: GREEN; Mode of pathogenicity: None; Publications: 24156116; Phenotypes: GM1 gangliosidosis MONDO:0018149, mucopolysaccharidosis type 4B MONDO:0009660; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal; Current diagnostic: yes | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.6207 | DIS3L2 |
Ken Lee Wan changed review comment from: Perlman syndrome is a well-established gene-disease association with autosomal recessive Perlman syndrome (https://search.clinicalgenome.org/CCID:004649) Perlman syndrome (PRLMNS) is an autosomal recessive congenital overgrowth syndrome with similarities to Beckwith-Wiedemann syndrome (BWS; 130650). Affected children are large at birth, are hypotonic and show organomegaly, characteristic facial dysmorphisms, renal anomalies, frequent neurodevelopmental delay and high neonatal mortality. Perlman syndrome is associated with a high risk of Wilms tumour (OMIM: 267000). PMID 16278893: 6 out of 22 patients have developmental delay PMID 22306653: 5 surviving patients with at least one loss-of-function variant identified have developmental delay. PMID 28328139: 1 surviving patient with compound heterozygous (splice site and missense variants) has developmental delay Mechanism of disease causation: loss of function; to: DIS3L2 is a well-established gene-disease association with autosomal recessive Perlman syndrome (https://search.clinicalgenome.org/CCID:004649) Perlman syndrome (PRLMNS) is an autosomal recessive congenital overgrowth syndrome with similarities to Beckwith-Wiedemann syndrome (BWS; 130650). Affected children are large at birth, are hypotonic and show organomegaly, characteristic facial dysmorphisms, renal anomalies, frequent neurodevelopmental delay and high neonatal mortality. Perlman syndrome is associated with a high risk of Wilms tumour (OMIM: 267000). PMID 16278893: 6 out of 22 patients have developmental delay PMID 22306653: 5 surviving patients with at least one loss-of-function variant identified have developmental delay. PMID 28328139: 1 surviving patient with compound heterozygous (splice site and missense variants) has developmental delay Mechanism of disease causation: loss of function |
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| Intellectual disability syndromic and non-syndromic v0.6124 | PNPLA8 |
Chirag Patel gene: PNPLA8 was added gene: PNPLA8 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: PNPLA8 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: PNPLA8 were set to PMID: 39082157 Phenotypes for gene: PNPLA8 were set to PNPLA8-related neurological diseases Review for gene: PNPLA8 was set to GREEN gene: PNPLA8 was marked as current diagnostic Added comment: Cohort analysis of clinical features of new and previously reported individuals with biallelic PNPLA8 variants (25 affected individuals across 20 families). They showed that PNPLA8-related neurological diseases manifest as a continuum ranging from variable developmental and/or degenerative epileptic-dyskinetic encephalopathy to childhood-onset neurodegeneration. Complete loss of PNPLA8 was associated with the more profound end of the spectrum. 13/19 individuals (info available) had developmental delay and/or severe intellectual disability. Using cerebral organoids generated from human induced pluripotent stem cells, they found that loss of PNPLA8 led to developmental defects by reducing the number of basal radial glial cells and upper-layer neurons. Neural progenitor cells lacking PNPLA8 showed a reduced amount of lysophosphatidic acid, lysophosphatidylethanolamine and phosphatidic acid. They show that PNPLA8 is crucial to meet phospholipid synthetic needs and to produce abundant basal radial glial cells in human brain development. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.6123 | TTL |
Mark Cleghorn gene: TTL was added gene: TTL was added to Intellectual disability syndromic and non-syndromic. Sources: Other Mode of inheritance for gene: TTL was set to BIALLELIC, autosomal or pseudoautosomal Phenotypes for gene: TTL were set to complex neurodevelopmental disorder MONDO:0100038 Review for gene: TTL was set to AMBER Added comment: TTL Valentina Serpieri, University of Pavia ESHG talk 1/6/24 FAM1 (Italy) 2 affected sisters born to consanguineous Pakistani parents GDD, spastic tetraparesis, optic atrophy, brain anomalies resembling tubulinopathies (dysplasia of corpus callosum, basal ganglia, brainstem) WES: homozygous TTL:c.1013G>A; p.Cys338Tyr in both affected sisters Via genematcher 5 more families (9 individuals) w similar phenotypes and biallelic variants in TTL FAM2 (Egypt): homozygous p.Arg46Pro FAM3 (Egypt): homozygous p.Arg46Pro FAM4 (Australia): homozygous p.Gln183Arg FAM5 (France): homozygous p.Trp147* FAM6 (Saudi Arabia): homozygous p.His243Tyr TTL KO mice: death soon after birth, no overt malformations, but defects in organisation of cerebral layers Functional work on patient fibroblasts FAM1 – reduced quantity of TTL protein compared to control on Western blot, decreased function of TTL protein (increase in detyrosinated tubulin) compared to controls – infer LoF as mechanism FAM3 – mentioned but no details FAM4– mentioned but no details Sources: Other |
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| Intellectual disability syndromic and non-syndromic v0.6121 | CSMD1 |
Krithika Murali gene: CSMD1 was added gene: CSMD1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: CSMD1 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: CSMD1 were set to PMID 38816421 Phenotypes for gene: CSMD1 were set to complex neurodevelopmental disorder MONDO:0100038 Review for gene: CSMD1 was set to GREEN Added comment: PMID 38816421 Werren et al 2024 report 8 individuals from 6 families with biallelic missense CSMD1 variants identified through exome sequencing and subsequent gene-sharing efforts. Shared phenotypic features included: GDD, ID, microcephaly and polymicrogyria. Other features included dysmorphism, IUGR, hypotonia, arthrogryposis, seizures, opthalmological anomalies and other brain white matter anomalies Heterozygous parents were unaffected. Loss of function is the postulated mechanism based on experimental data involving early-stage forebrain organoids differentiated from CSMD1 knockout human embryonic stem cells. ClinGen haploinsufficiency score of 1, however, this curation was last reviewed in 2018. This gene is within the scope of review for the ClinGen Autisim and ID GCEP. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.6090 | SLC39A14 | Zornitza Stark Phenotypes for gene: SLC39A14 were changed from to Hypermanganesemia with dystonia 2 (MIM# 617013) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.6063 | SLC39A14 | Kushani Jayasinghe reviewed gene: SLC39A14: Rating: GREEN; Mode of pathogenicity: None; Publications: PMID: 27231142, 29685658; Phenotypes: Hypermanganesemia with dystonia 2; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.5881 | THRA |
Hnin Aung changed review comment from: Over 10 sequence variants (including truncating nonsense and frameshift as well as missense) have been reported in the literature in association with consistent phenotype of mild hypothyroidism (growth retardation, relatively high birth length and weight, mild-to-moderate mental retardation, mild skeletal dysplasia, delayed dentition and constipation) and specific facial features. Milder outcomes for missense variants and more severe phenotype manifestation for truncating variants have been observed. Most of the variants are located in the last exon of the THRA isoform 1 (NM_199334.5; a shorter isoform) affecting the C-terminal ligand binding domain with nonsense and frameshift variants predicted to escape nonsense mediated decay. These variants are either de novo or inherited from an affected parent. A few pedigrees are also available with segregation data. Truncating variants appear to have near complete penetrance whereas missense variants may be associated with variable expressivity (Family C - PMID: 27144938). Functional evidence suggests altered gene product with possible dominant negative effect (PMID: 22168587, 28471274). Knock in mouse model available for E403X presenting with similar phenotype as seen in the human patients, including growth retardation and variable presentation of psychomotor deficit (PMID: 32924834). A small number THRA sequence variant (missense) reported among autism cohort [PMID: 28856816, 25621899].; to: Over 10 sequence variants (including truncating nonsense and frameshift as well as missense) have been reported in the literature in association with consistent phenotype of mild hypothyroidism (growth retardation, relatively high birth length and weight, mild-to-moderate mental retardation, mild skeletal dysplasia, delayed dentition and constipation) and specific facial features. Milder outcomes for missense variants and more severe phenotype manifestations for truncating variants have been observed. Most of the variants are located in the last exon of the THRA isoform 1 (NM_199334.5; a shorter isoform) affecting the C-terminal ligand binding domain with nonsense and frameshift variants predicted to escape nonsense mediated decay. These variants are either de novo or inherited from an affected parent. A few pedigrees are also available with segregation data. Truncating variants appear to have near complete penetrance whereas missense variants may be associated with variable expressivity (Family C - PMID: 27144938). Functional evidence suggests altered gene product with possible dominant negative effect (PMID: 22168587, 28471274). Knock in mouse model available for E403X presenting with similar phenotype as seen in the human patients, including growth retardation and variable presentation of psychomotor deficit (PMID: 32924834). A small number THRA sequence variant (missense) reported among autism cohort [PMID: 28856816, 25621899]. |
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| Intellectual disability syndromic and non-syndromic v0.5881 | THRA |
Hnin Aung changed review comment from: Over 10 sequence variants (including truncating nonsense and frameshift as well as missense) have been reported in the literature in association with consistent phenotype of mild hypothyroidism (growth retardation, relatively high birth length and weight, mild-to-moderate mental retardation, mild skeletal dysplasia, delayed dentition and constipation) and specific facial features. Milder outcomes for missense variants and more severe phenotype manifestation for truncating variants have been observed. Most of the variants are located in the last exon of the THRA isoform 1 (NM_199334.5; a shorter isoform) affecting the C-terminal ligand binding domain with nonsense and frameshift variants predicted to escape nonsense mediated decay. These variants are either de novo or inherited from an affected parent. A few pedigrees are also available with segregation data. Truncating variants appear to have near complete penetrance whereas missense variants may be associated with variable expressivity (Family C - PMID: 27144938). Functional evidence suggests altered gene product with possible dominant negative effect (PMID: 22168587, 28471274). Knock in mouse model available for E403X presenting with similar phenotype as seen in the human patients, including growth retardation and variable presentation of psychomotor deficit (PMID: 32924834). A small number THRA sequence variant (missense) reported among autism cohort [PMID: 28856816, 25621899].; to: Over 10 sequence variants (including truncating nonsense and frameshift as well as missense) have been reported in the literature in association with consistent phenotype of mild hypothyroidism (growth retardation, relatively high birth length and weight, mild-to-moderate mental retardation, mild skeletal dysplasia, delayed dentition and constipation) and specific facial features. Milder outcomes for missense variants and more severe phenotype manifestation for truncating variants have been observed. Most of the variants are located in the last exon of the THRA isoform 1 (NM_199334.5; a shorter isoform) affecting the C-terminal ligand binding domain with nonsense and frameshift variants predicted to escape nonsense mediated decay. These variants are either de novo or inherited from an affected parent. A few pedigrees are also available with segregation data. Truncating variants appear to have near complete penetrance whereas missense variants may be associated with variable expressivity (Family C - PMID: 27144938). Functional evidence suggests altered gene product with possible dominant negative effect (PMID: 22168587, 28471274). Knock in mouse model available for E403X presenting with similar phenotype as seen in the human patients, including growth retardation and variable presentation of psychomotor deficit (PMID: 32924834). A small number THRA sequence variant (missense) reported among autism cohort [PMID: 28856816, 25621899]. |
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| Intellectual disability syndromic and non-syndromic v0.5878 | SLC19A3 | Jane Lin reviewed gene: SLC19A3: Rating: GREEN; Mode of pathogenicity: None; Publications: PMID: 15871139, PMID: 34276785, PMID: 23482991, PMID: 20065143; Phenotypes: # 607483 BASAL GANGLIA DISEASE, BIOTIN-THIAMINE RESPONSIVE (BBTGD), THIAMINE METABOLISM DYSFUNCTION SYNDROME 2; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.5660 | CACHD1 |
Suliman Khan gene: CACHD1 was added gene: CACHD1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: CACHD1 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: CACHD1 were set to PMID: 38158856 Phenotypes for gene: CACHD1 were set to syndromic complex neurodevelopmental disorder MONDO:0800439 Penetrance for gene: CACHD1 were set to unknown Review for gene: CACHD1 was set to GREEN Added comment: PMID: 38158856 - Six affected individuals from four unrelated families with homozygous CACHD1 variants (3 splice, 2 frameshift and 1 nonsense variant). Excluding the two fatal cases, all other were affected by syndromic neurodevelopmental abnormalities, multiple organ systems featuring global impairment of psychomotor development, dysmorphic facial features, genitourinary abnormalities, oculo-auricular and congenital malformation. Seizure was reported in one case. Whole exome sequencing identified bi-allelic loss of function variants in the CACHD1 gene. In vitro human neural models of CACHD1 depletion displayed dysregulated of Wnt signaling in the developing brain. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.5479 | MCCC1 | Bryony Thompson Phenotypes for gene: MCCC1 were changed from to 3-Methylcrotonyl-CoA carboxylase 1 deficiency MIM#210200; Organic acidurias | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.5475 | MCCC1 | Bryony Thompson reviewed gene: MCCC1: Rating: AMBER; Mode of pathogenicity: None; Publications: 36822454, 31730530; Phenotypes: 3-Methylcrotonyl-CoA carboxylase 1 deficiency MIM#210200, Organic acidurias; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.5399 | SDHA | Claire Fryer-Smith reviewed gene: SDHA: Rating: GREEN; Mode of pathogenicity: None; Publications: 1492653, 23322652; Phenotypes: Cardiomyopathy, dilated, 1GG MIM#613642, Mitochondrial complex II deficiency, nuclear type 1 MIM#252011, Neurodegeneration with ataxia and late-onset optic atrophy MIM#619259, Paragangliomas MIM#614165; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.5278 | PIP5K1C |
Chirag Patel gene: PIP5K1C was added gene: PIP5K1C was added to Intellectual disability syndromic and non-syndromic. Sources: Other Mode of inheritance for gene: PIP5K1C was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Phenotypes for gene: PIP5K1C were set to Neurodevelopmental disorder and microcephaly Review for gene: PIP5K1C was set to GREEN gene: PIP5K1C was marked as current diagnostic Added comment: ESHG 2023: 9 unrelated patients with de novo missense variants in PIP5K1C (3 x recurrent variants). Presentation with DD/ID (mod-profound), microcephaly, seizures, visual impairment, and dysmorphism. PIP5K1C is one of the phosphoinositolides, which control membrane composition of organelles and varying cellular processes. Patient fibroblasts showed increased PI(4,5)P2 levels, altered PI(4,5)P2 composition of early endosomes, and impaired endocytosis trafficking. Drosophila models showed microcephaly and ocular phenotype. Sources: Other |
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| Intellectual disability syndromic and non-syndromic v0.5127 | SETD2 |
Zornitza Stark edited their review of gene: SETD2: Added comment: PMID 32710489: 12 unrelated patients, ranging from 1 month to 12 years of age, with a multisystemic neurodevelopmental disorder associated with a specific de novo heterozygous mutation in the SETD2 gene (R1740W). Key clinical features: severely impaired global development apparent from infancy, feeding difficulties with failure to thrive, small head circumference, and dysmorphic facial features. Affected individuals have impaired intellectual development and hypotonia; they do not achieve walking or meaningful speech. Other neurologic findings may include seizures, hearing loss, ophthalmologic defects, and brain imaging abnormalities. There is variable involvement of other organ systems, including skeletal, genitourinary, cardiac, and possibly endocrine. Further 3 unrelated patients identified with mild to moderately impaired intellectual development associated with a specific de novo heterozygous mutation in the SETD2 gene (R1740Q). These are distinct clinically from Luscan-Lumish syndrome, which is characterised by overgrowth.; Changed publications: 29681085, 32710489; Changed phenotypes: Luscan-Lumish syndrome, MIM#616831, Rabin-Pappas syndrome,MIM# 620155, Intellectual developmental disorder, autosomal dominant 70, MIM# 620157 |
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| Intellectual disability syndromic and non-syndromic v0.5052 | FEM1C |
Paul De Fazio gene: FEM1C was added gene: FEM1C was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: FEM1C was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: FEM1C were set to 36336956; 28135719; 33398170; 33398168 Phenotypes for gene: FEM1C were set to Neurodevelopmental disorder, FEM1C-related MONDO:0700092 Review for gene: FEM1C was set to GREEN gene: FEM1C was marked as current diagnostic Added comment: PMID:36336956 describes a 9-year-old boy with severe DD, lack of speech, pyramidal signs, and limb ataxia who had a de novo missense variant Asp126His in FEM1C ascertained by WES. The equivalent variant introduced into the nematode C.elegans resulted in disabled locomotion caused by synaptic abnormalities and not muscle dysfunction. An alternate change Asp126Val was reported in the DDD study de novo in a patient with uncharacterised developmental delay (PMID:28135719). The Asp126 residue (but not either of the variants above specifically) was shown to be functionally important by in vitro studies (PMID:33398170;33398168). The residue is highly conserved and located in a region of missense constraint. Borderline green, 2 patients and an animal model. Note all evidence points to the Asp126 residue being of specific importance. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.5031 | KIF26A |
Chirag Patel gene: KIF26A was added gene: KIF26A was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: KIF26A was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: KIF26A were set to PMID: 36228617 Phenotypes for gene: KIF26A were set to Congenital brain malformations, no OMIM # Review for gene: KIF26A was set to GREEN Added comment: 5 unrelated patients with biallelic loss-of-function variants in KIF26A (found through WES), exhibiting a spectrum of congenital brain malformations (schizencephaly, corpus callosum anomalies, polymicrgyria, and ventriculomegaly). Combining mice and human iPSC-derived organoid models, they discovered that loss of KIF26A causes excitatory neuron-specific defects in radial migration, localization, dendritic and axonal growth, and apoptosis, offering a convincing explanation of the disease etiology in patients. Single-cell RNA sequencing in KIF26A knockout organoids revealed transcriptional changes in MAPK, MYC, and E2F pathways. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.4959 | NSD2 | Zornitza Stark edited their review of gene: NSD2: Added comment: PMID 36189577: two individuals reported with a GoF variant, p.Glu1099Lys, and a distinct phenotype: intellectual disability, coarse/ square facial gestalt, abnormalities of the hands, and organomegaly.; Changed publications: 30345613, 31171569, 36189577; Changed phenotypes: Rauch-Steindl syndrome, MIM# 619695, Microcephaly, intellectual disability, Neurodevelopmental disorder, NSD2-associated, GoF, MONDO:0700092 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.4517 | HIST1H4F |
Elena Savva edited their review of gene: HIST1H4F: Added comment: PMID: 35202563 - single de novo missense in a patient with neurodevelopmental features of intellectual disability and motor and/or gross developmental delay. - zebrafish studies show a significant increase in all of mild dev delay, necrosis, defective organogenesis and pre-gastrulation failure Sources: Literature; Changed rating: AMBER |
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| Intellectual disability syndromic and non-syndromic v0.4517 | HIST1H4F |
Elena Savva gene: HIST1H4F was added gene: HIST1H4F was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: HIST1H4F was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: HIST1H4F were set to PMID: 35202563 Phenotypes for gene: HIST1H4F were set to Neurodevelopmental disorders Review for gene: HIST1H4F was set to GREEN Added comment: PMID: 35202563 - single de novo missense in a patient with neurodevelopmental features of intellectual disability and motor and/or gross developmental delay. - zebrafish studies show a significant increase in all of mild dev delay, necrosis, defective organogenesis and pre-gastrulation failure Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.4515 | HIST1H4I |
Elena Savva gene: HIST1H4I was added gene: HIST1H4I was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: HIST1H4I was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: HIST1H4I were set to PMID: 35202563 Phenotypes for gene: HIST1H4I were set to Neurodevelopmental syndrome Review for gene: HIST1H4I was set to GREEN Added comment: PMID: 35202563 - 3 unrelated de novo patients, p.His75Arg was recurring and observed in 2/3 probands. - Zebrafish study shows both variants resulted in a significant increases in developmental issues such as in mild dev delay, necrosis and defective organogenesis. - All patients had intellectual disability and motor and/or gross developmental delay and dysmorphisms. - 2/3 patients showed bilateral conductive hearing loss Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.4345 | CLCN7 |
Zornitza Stark gene: CLCN7 was added gene: CLCN7 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: CLCN7 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: CLCN7 were set to 31155284 Phenotypes for gene: CLCN7 were set to Hypopigmentation, organomegaly, and delayed myelination and development, MIM# 618541 Mode of pathogenicity for gene: CLCN7 was set to Loss-of-function variants (as defined in pop up message) DO NOT cause this phenotype - please provide details in the comments Review for gene: CLCN7 was set to AMBER Added comment: Two individuals reported with same missense variant and hypopigmentation, organomegaly, and delayed myelination and development. Variant is GoF. No osteopetrosis, biopsy findings from skin and other organs are consistent with a lysosomal storage disorder. IUGR, prematurity and polyhydramnios are features. Bi-allelic variants in this gene are associated with osteopetrosis. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.4179 | BCL11A | Zornitza Stark Phenotypes for gene: BCL11A were changed from to Dias-Logan syndrome, MIM# 617101 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.4176 | BCL11A | Zornitza Stark reviewed gene: BCL11A: Rating: GREEN; Mode of pathogenicity: None; Publications: 27453576, 32903878; Phenotypes: Dias-Logan syndrome, MIM# 617101; Mode of inheritance: MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.4020 | CLCN3 |
Zornitza Stark gene: CLCN3 was added gene: CLCN3 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: CLCN3 was set to BOTH monoallelic and biallelic (but BIALLELIC mutations cause a more SEVERE disease form), autosomal or pseudoautosomal Publications for gene: CLCN3 were set to 34186028 Phenotypes for gene: CLCN3 were set to Neurodevelopmental disorder Mode of pathogenicity for gene: CLCN3 was set to Other Review for gene: CLCN3 was set to GREEN Added comment: 11 individuals reported, 9 that carried 8 different rare heterozygous missense variants in CLCN3, and 2 siblings that were homozygous for an NMD-predicted frameshift variant likely abolishing ClC-3 function. All missense variants were confirmed to be de novo in eight individuals for whom parental data was available. The 11 individuals in the cohort share clinical features of variable severity. All 11 have GDD or ID and dysmorphic features, and a majority has mood or behavioural disorders and structural brain abnormalities: - Structural brain abnormalities on MRI (9/11) included partial or full agenesis of the corpus callosum (6/9), disorganized cerebellar folia (4/9), delayed myelination (3/9), decreased white matter volume (3/9), pons hypoplasia (3/9), and dysmorphic dentate nuclei (3/9). Six of those with brain abnormalities also presented with seizures. - Nine have abnormal vision, including strabismus in four and inability to fix or follow in the two with homozygous loss-of-function variants. - Hypotonia ranging from mild to severe was reported in 7 of the 11 individuals. - Six have mood or behavioural disorders, particularly anxiety (3/6). - Consistent dysmorphic facial features included microcephaly, prominent forehead, hypertelorism, down-slanting palpebral fissures, full cheeks, and micrognathia. The severity of disease in the two siblings with homozygous disruption of ClC-3 is consistent with the drastic phenotype seen in Clcn3 KO mice. The disease was more severe in two siblings carrying homozygous loss-of-function variants with the presence of GDD, absent speech, seizures, and salt and pepper fundal pigmentation in both individuals, with one deceased at 14 months of age. The siblings also had significant neuroanatomical findings including diffusely decreased white matter volume, thin corpora callosa, small hippocampi, and disorganized cerebellar folia. Supporting biallelic inheritance for LoF variants, disruption of mouse Clcn3 results in drastic neurodegeneration with loss of the hippocampus a few months after birth and early retinal degeneration. Clcn3−/− mice display severe neurodegeneration, whereas heterozygous Clcn3+/− mice appear normal. Patch-clamp studies were used to investigate four of the missense variants. These suggested a gain of function in two variants with increased current in HEK cells, however they also showed reduced rectification of voltage and a loss of transient current, plus decreased current amplitude, glycosylation and surface expression when expressed in oocytes, and were suspected to interfere with channel gating and a negative feedback mechanism. These effects were also shown to vary depending on pH levels. The current of the remaining two variants did not differ from WT. For heterozygous missense variants, the disruption induced may be at least partially conferred to mutant/WT homodimers and mutant/ClC-4 heterodimers. Both loss and gain of function in this gene resulted in the same phenotype. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.4016 | SPTBN1 |
Belinda Chong changed review comment from: PMID: 34211179 - Heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays; mild to severe intellectual disability; autistic features; seizures; behavioral and movement abnormalities; hypotonia; and variable dysmorphic facial features. - Show that these SPTBN1 variants lead to effects that affect βII-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. PMID: 33847457 - Common features include global developmental delays, intellectual disability, and behavioral disturbances. Autistic features (4/6) and epilepsy (2/7) or abnormal electroencephalogram without overt seizures (1/7) were present in a subset. - identified seven unrelated individuals with heterozygous SPTBN1 variants: two with de novo missense variants and five with predicted loss-of-function variants (found to be de novo in two, while one was inherited from a mother with a history of learning disabilities). - Identification of loss-of-function variants suggests a haploinsufficiency mechanism, but additional functional studies are required to fully elucidate disease pathogenesis. Sources: Literature Sources: Literature; to: PMID: 34211179 - Heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays; mild to severe intellectual disability; autistic features; seizures (9/29); behavioral and movement abnormalities; hypotonia; and variable dysmorphic facial features. - Show that these SPTBN1 variants lead to effects that affect βII-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. PMID: 33847457 - Common features include global developmental delays, intellectual disability, and behavioral disturbances. Autistic features (4/6) and epilepsy (2/7) or abnormal electroencephalogram without overt seizures (1/7) were present in a subset. - identified seven unrelated individuals with heterozygous SPTBN1 variants: two with de novo missense variants and five with predicted loss-of-function variants (found to be de novo in two, while one was inherited from a mother with a history of learning disabilities). - Identification of loss-of-function variants suggests a haploinsufficiency mechanism, but additional functional studies are required to fully elucidate disease pathogenesis. Sources: Literature Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.4015 | SPTBN1 |
Belinda Chong gene: SPTBN1 was added gene: SPTBN1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: SPTBN1 was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: SPTBN1 were set to PMID: 34211179 PMID: 33847457 Phenotypes for gene: SPTBN1 were set to Neurodevelopmental Syndrome Review for gene: SPTBN1 was set to GREEN Added comment: PMID: 34211179 - Heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays; mild to severe intellectual disability; autistic features; seizures; behavioral and movement abnormalities; hypotonia; and variable dysmorphic facial features. - Show that these SPTBN1 variants lead to effects that affect βII-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. PMID: 33847457 - Common features include global developmental delays, intellectual disability, and behavioral disturbances. Autistic features (4/6) and epilepsy (2/7) or abnormal electroencephalogram without overt seizures (1/7) were present in a subset. - identified seven unrelated individuals with heterozygous SPTBN1 variants: two with de novo missense variants and five with predicted loss-of-function variants (found to be de novo in two, while one was inherited from a mother with a history of learning disabilities). - Identification of loss-of-function variants suggests a haploinsufficiency mechanism, but additional functional studies are required to fully elucidate disease pathogenesis. Sources: Literature Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3967 | RING1 |
Zornitza Stark gene: RING1 was added gene: RING1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: RING1 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: RING1 were set to 29386386 Phenotypes for gene: RING1 were set to microcephaly; intellectual disability Review for gene: RING1 was set to RED Added comment: Not associated with any phenotype in OMIM. PMID: 29386386 - Pierce et al 2018 - report a 13 yo female with a de novo RING1 p.R95Q variant and syndromic neurodevelopmental disabilities. Early motor and language development were normal but were delayed after the first year of life. Cognitive testing showed a verbal IQ of 55 and a visual performance IQ of 63. Head circumference at birth was -4.9 SD, and -4.2 SD at age 13 which falls into the severe microcephaly category. C. elegans with either the missense mutation or complete knockout of spat-3 (the suggested RING1 ortholog) were defective in monoubiquitylation of histone H2A and had defects in neuronal migration and axon guidance. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3862 | FARSA |
Chirag Patel gene: FARSA was added gene: FARSA was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: FARSA was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: FARSA were set to PMID: 33598926 Phenotypes for gene: FARSA were set to Rajab interstitial lung disease with brain calcifications 2 Review for gene: FARSA was set to GREEN gene: FARSA was marked as current diagnostic Added comment: FARSA is a subunit with FARSB to form FARS1 enzyme. Bi-allelic mutations in FARSB are well described. Schuch et al. (2021) report 3 unrelated individuals with bi-allelic variants in FARSA. Identified through WES and variants segregated with disease. Functional evidence was obtained with reduced FARS1 enzyme activity levels in fibroblasts or EBV-transformed lymphoblastoid cell lines (EBV-LCLs) of patients. Common to all was a chronic interstitial lung disease starting early in life and characterized by bilateral ground-glass opacification on HR-CT, and cholesterol pneumonitis in lung histology. Additional abnormalities in other organ systems include liver disease, neurological manifestations, and growth restriction. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3786 | UFSP2 |
Konstantinos Varvagiannis changed review comment from: Ni et al (2021 - PMID: 33473208) describe the phenotype of 8 children (belonging to 4 families - 2 of which consanguineous) homozygous for a UFSP2 missense variant [NM_018359.5:c.344T>A; p.(Val115Glu)]. Members of a broader consanguineous pedigree from Pakistan with 3 affected children with epilepsy and DD and ID underwent exome sequencing. All affected individuals were homozygous for the specific SNV with their parents (2 parent pairs, in both cases first cousins) being heterozygous. An unaffected sib was homozygous for the wt allele. Through genematching platforms 3 additional families with similarly affected individuals and homozygosity for the same variant were recruited. These additional families were from Pakistan (1/3) and Afganistan (2/3). Based on ROH analysis from the broader first pedigree and an additional family the authors concluded on a single shared region of homozygosity on chr 4q. Lack of ES data did not allow verification of whether 2/4 families shared the same haplotype with the other 2. The authors calculated the probability of the genotype-phenotype cosegragation occurring by chance (0.009) and this was lower than the recommended criterion (0.06) for strong evidence of pathogenicity. Shared features included abnormal tone in most (hypotonia 6/8, limb hypertonia 1/8), seizures (8/8 - onset 2d - 7m), severe DD with speech delay/absent speech (8/8), ID (8/8), strabismus (6/8). UFSP2 encodes UFM1-specific protease 2 involved in UFmylation, a post-translational protein modification. As summarized by the authors the cysteine protease encoded by this gene (as is also the case for UFSP1) cleaves UFM1 in the initial step of UFMylation. Apart from producing mature UFM1, the 2 proteases have also the ability to release UFM1 from UFMylated proteins, in the process of de-UFMylation. [several refs. provided] UFMylation is important in brain development with mutations in genes encoding other components of the pathway reported in other NDD disorders (incl. UFM1, UBA5, UFC1). Additional studies were carried to provide evidence for pathogenicity of this variant. Skin biopsies from 3 individuals were carried out to establish fibroblast cultures. Immunoblotting revealed reduced UFSP2 levels relative to controls. mRNA levels measured by qRT-PCR revealed no differences compared to controls altogether suggesting normal mRNA but reduced protein stability. The authors demonstrated increased levels of UFM1-conjugated proteins (incl. DDRGK1, or TRIP4). Ectopic expression of wt UFSP2 normalized the levels of UFMylated proteins in the fibroblasts which was not the case for the V115E variant. Further the variant was difficult to detect by immunoblotting consistent with an effect on protein destabilization. Although disruption of UFMylation induces ER stress, this was not shown to occur in patient fibroblast lines, when assessed for ER stress markers. Evaluation of data from the GTEx project, concerning UFSP2 as well as well as DDRGK1 or TRIP4 - an UFMylation target - revealed relevant expression in multiple regions of the human brain. Overall the authors provide evidence for defective de-UFMylation in patient fibroblasts (presence of increased UFMylation marks). The authors stress out that the effect of the variant in UFMylation in brain is unknown, as UFSP1 or other enzymes might compensate in the presence of hypomorphic UFSP2 mutants. Biallelic UFSP2 variants have previously been reported in 2 skeletal dysplasias [# 142669. BEUKES HIP DYSPLASIA; BHD and # 617974. SPONDYLOEPIMETAPHYSEAL DYSPLASIA, DI ROCCO TYPE; SEMDDR]. These disorders are not characterized by neurological dysfunction or epilepsy. The authors underscore the fact that variants identified in these disorders (Y290H, D526A, H428R) localize within the C-terminal catalytic (peptidase) domain [aa 278 – 461] while the variant here identified lies in the N-terminal substrate binding domain affecting protein stability/abundance. In OMIM, only the 2 aforementioned disorders are currently associated with biallelic UFSP2 mutations. There is no associated phenotype in G2P. SysID includes UFSP2 among the primary ID genes. You may consider inclusion in the current panel with amber/green rating. Sources: Literature; to: Ni et al (2021 - PMID: 33473208) describe the phenotype of 8 children (belonging to 4 families - 2 of which consanguineous) homozygous for a UFSP2 missense variant [NM_018359.5:c.344T>A; p.(Val115Glu)]. Members of a broader consanguineous pedigree from Pakistan with 3 affected children with epilepsy and DD and ID underwent exome sequencing. All affected individuals were homozygous for the specific SNV with their parents (2 parent pairs, in both cases first cousins) being heterozygous. An unaffected sib was homozygous for the wt allele. Through genematching platforms 3 additional families with similarly affected individuals and homozygosity for the same variant were recruited. These additional families were from Pakistan (1/3) and Afganistan (2/3). Based on ROH analysis from the broader first pedigree and an additional family the authors concluded on a single shared region of homozygosity on chr 4q. Lack of ES data did not allow verification of whether 2/4 families shared the same haplotype with the other 2. The authors calculated the probability of the genotype-phenotype cosegragation occurring by chance (0.009) and this was lower than the recommended criterion (0.06) for strong evidence of pathogenicity. Shared features included abnormal tone in most (hypotonia 6/8, limb hypertonia 1/8), seizures (8/8 - onset 2d - 7m), severe DD with speech delay/absent speech (8/8), ID (8/8), strabismus (6/8). UFSP2 encodes UFM1-specific protease 2 involved in UFmylation, a post-translational protein modification. As summarized by the authors the cysteine protease encoded by this gene (as is also the case for UFSP1) cleaves UFM1 in the initial step of UFMylation. Apart from producing mature UFM1, the 2 proteases have also the ability to release UFM1 from UFMylated proteins, in the process of de-UFMylation. [several refs. provided] UFMylation is important in brain development with mutations in genes encoding other components of the pathway reported in other NDD disorders (incl. UFM1, UBA5, UFC1). Additional studies were carried to provide evidence for pathogenicity of this variant. Skin biopsies from 3 individuals were carried out to establish fibroblast cultures. Immunoblotting revealed reduced UFSP2 levels relative to controls. mRNA levels measured by qRT-PCR revealed no differences compared to controls altogether suggesting normal mRNA but reduced protein stability. The authors demonstrated increased levels of UFM1-conjugated proteins (incl. DDRGK1, or TRIP4). Ectopic expression of wt UFSP2 normalized the levels of UFMylated proteins in the fibroblasts which was not the case for the V115E variant. Further the variant was difficult to detect by immunoblotting consistent with an effect on protein destabilization. Although disruption of UFMylation induces ER stress, this was not shown to occur in patient fibroblast lines, when assessed for ER stress markers. Evaluation of data from the GTEx project, concerning UFSP2 as well as well as DDRGK1 or TRIP4 - an UFMylation target - revealed relevant expression in multiple regions of the human brain. Overall the authors provide evidence for defective de-UFMylation in patient fibroblasts (presence of increased UFMylation marks). The authors stress out that the effect of the variant in UFMylation in brain is unknown, as UFSP1 or other enzymes might compensate in the presence of hypomorphic UFSP2 mutants. **Monoallelic** (correction to previous review) UFSP2 variants have previously been reported in 2 skeletal dysplasias [# 142669. BEUKES HIP DYSPLASIA; BHD and # 617974. SPONDYLOEPIMETAPHYSEAL DYSPLASIA, DI ROCCO TYPE; SEMDDR]. These disorders are not characterized by neurological dysfunction or epilepsy. The authors underscore the fact that variants identified in these disorders (Y290H, D526A, H428R) localize within the C-terminal catalytic (peptidase) domain [aa 278 – 461] while the variant here identified lies in the N-terminal substrate binding domain affecting protein stability/abundance. In OMIM, only the 2 aforementioned disorders are currently associated with biallelic UFSP2 mutations. There is no associated phenotype in G2P. SysID includes UFSP2 among the primary ID genes. You may consider inclusion in the current panel with amber/green rating. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3785 | UFSP2 |
Konstantinos Varvagiannis gene: UFSP2 was added gene: UFSP2 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: UFSP2 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: UFSP2 were set to 33473208 Phenotypes for gene: UFSP2 were set to Abnormal muscle tone; Seizures; Global developmental delay; Delayed speech and language development; Intellectual disability; Strabismus Penetrance for gene: UFSP2 were set to Complete Review for gene: UFSP2 was set to AMBER Added comment: Ni et al (2021 - PMID: 33473208) describe the phenotype of 8 children (belonging to 4 families - 2 of which consanguineous) homozygous for a UFSP2 missense variant [NM_018359.5:c.344T>A; p.(Val115Glu)]. Members of a broader consanguineous pedigree from Pakistan with 3 affected children with epilepsy and DD and ID underwent exome sequencing. All affected individuals were homozygous for the specific SNV with their parents (2 parent pairs, in both cases first cousins) being heterozygous. An unaffected sib was homozygous for the wt allele. Through genematching platforms 3 additional families with similarly affected individuals and homozygosity for the same variant were recruited. These additional families were from Pakistan (1/3) and Afganistan (2/3). Based on ROH analysis from the broader first pedigree and an additional family the authors concluded on a single shared region of homozygosity on chr 4q. Lack of ES data did not allow verification of whether 2/4 families shared the same haplotype with the other 2. The authors calculated the probability of the genotype-phenotype cosegragation occurring by chance (0.009) and this was lower than the recommended criterion (0.06) for strong evidence of pathogenicity. Shared features included abnormal tone in most (hypotonia 6/8, limb hypertonia 1/8), seizures (8/8 - onset 2d - 7m), severe DD with speech delay/absent speech (8/8), ID (8/8), strabismus (6/8). UFSP2 encodes UFM1-specific protease 2 involved in UFmylation, a post-translational protein modification. As summarized by the authors the cysteine protease encoded by this gene (as is also the case for UFSP1) cleaves UFM1 in the initial step of UFMylation. Apart from producing mature UFM1, the 2 proteases have also the ability to release UFM1 from UFMylated proteins, in the process of de-UFMylation. [several refs. provided] UFMylation is important in brain development with mutations in genes encoding other components of the pathway reported in other NDD disorders (incl. UFM1, UBA5, UFC1). Additional studies were carried to provide evidence for pathogenicity of this variant. Skin biopsies from 3 individuals were carried out to establish fibroblast cultures. Immunoblotting revealed reduced UFSP2 levels relative to controls. mRNA levels measured by qRT-PCR revealed no differences compared to controls altogether suggesting normal mRNA but reduced protein stability. The authors demonstrated increased levels of UFM1-conjugated proteins (incl. DDRGK1, or TRIP4). Ectopic expression of wt UFSP2 normalized the levels of UFMylated proteins in the fibroblasts which was not the case for the V115E variant. Further the variant was difficult to detect by immunoblotting consistent with an effect on protein destabilization. Although disruption of UFMylation induces ER stress, this was not shown to occur in patient fibroblast lines, when assessed for ER stress markers. Evaluation of data from the GTEx project, concerning UFSP2 as well as well as DDRGK1 or TRIP4 - an UFMylation target - revealed relevant expression in multiple regions of the human brain. Overall the authors provide evidence for defective de-UFMylation in patient fibroblasts (presence of increased UFMylation marks). The authors stress out that the effect of the variant in UFMylation in brain is unknown, as UFSP1 or other enzymes might compensate in the presence of hypomorphic UFSP2 mutants. Biallelic UFSP2 variants have previously been reported in 2 skeletal dysplasias [# 142669. BEUKES HIP DYSPLASIA; BHD and # 617974. SPONDYLOEPIMETAPHYSEAL DYSPLASIA, DI ROCCO TYPE; SEMDDR]. These disorders are not characterized by neurological dysfunction or epilepsy. The authors underscore the fact that variants identified in these disorders (Y290H, D526A, H428R) localize within the C-terminal catalytic (peptidase) domain [aa 278 – 461] while the variant here identified lies in the N-terminal substrate binding domain affecting protein stability/abundance. In OMIM, only the 2 aforementioned disorders are currently associated with biallelic UFSP2 mutations. There is no associated phenotype in G2P. SysID includes UFSP2 among the primary ID genes. You may consider inclusion in the current panel with amber/green rating. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3679 | PLCH1 |
Zornitza Stark gene: PLCH1 was added gene: PLCH1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: PLCH1 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: PLCH1 were set to 33820834 Phenotypes for gene: PLCH1 were set to Holoprosencephaly spectrum; Severe developmental delay; Brain malformations Review for gene: PLCH1 was set to AMBER Added comment: PMID: 33820834 (2021) - Two sibling pairs from two unrelated families with a holoprosencephaly spectrum phenotype and different homozygous PLCH1 variants (c.2065C>T, p.Arg689* and c.4235delA, p.Cys1079ValfsTer16, respectively). One family presented with congenital hydrocephalus, epilepsy, significant developmental delay and a monoventricle or fused thalami; while sibs from the second family had alobar holoprosencephaly and cyclopia. 3/4 individuals also displayed a cleft palate and congenital heart disease. Human embryo immunohistochemistry showed PLCH1 to be expressed in the notorcord, developing spinal cord (in a ventral to dorsal gradient), dorsal root ganglia, cerebellum and dermatomyosome. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3401 | CBY1 |
Bryony Thompson gene: CBY1 was added gene: CBY1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: CBY1 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: CBY1 were set to 33131181; 25103236; 25220153 Phenotypes for gene: CBY1 were set to intellectual disability; cerebellar ataxia; molar tooth sign; polydactyly; Joubert syndrome Review for gene: CBY1 was set to GREEN Added comment: Three cases in two unrelated consanguineous families with homozygous loss of function variants, with ID as a feature of the phenotype. Multiple null model organisms recapitulate the human phenotype: Null mouse model had cystic kidneys, a phenotype common to ciliopathies. Reducing Cby levels in Xenopus laevis model reduced the density of multiciliated cells, the number of basal bodies per multiciliated cell, and the numbers of neural tube primary cilia; it also led to abnormal development of the neural crest, central nervous system, and pronephros. Depletion of cby1 in zebrafish results in ciliopathy‐related phenotypes. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.3062 | VPS41 |
Zornitza Stark gene: VPS41 was added gene: VPS41 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: VPS41 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: VPS41 were set to 32808683 Phenotypes for gene: VPS41 were set to Dystonia; intellectual disability Review for gene: VPS41 was set to RED Added comment: Single individual reported with homozygous canonical splice site variant resulting in exon 7 skipping, and global developmental delay and generalized dystonia. He attained a few words and voluntary limb movements but never sat unsupported. He had pale optic discs and an axonal neuropathy. From 6 years of age, his condition began to deteriorate, with reduced motor abilities and alertness. An MRI of the brain showed atrophy of the superior cerebellar vermis and slimming of the posterior limb of the corpus callosum. VPS41 is component of the HOPS complex and other genes in the complex have been implicated in movement disorders. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.2750 | PAX1 |
Konstantinos Varvagiannis gene: PAX1 was added gene: PAX1 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature,Radboud University Medical Center, Nijmegen Mode of inheritance for gene: PAX1 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: PAX1 were set to 29681087; 23851939; 28657137 Phenotypes for gene: PAX1 were set to Otofaciocervical syndrome 2, 615560 Penetrance for gene: PAX1 were set to Complete Review for gene: PAX1 was set to AMBER Added comment: Biallelic PAX1 pathogenic variants cause Otofaciocervical syndrome 2 (OMIM 615560). Brief review of the literature suggests 3 relevant publications to date (04-07-2020). 2 individuals with DD and ID have been reported (Patil et al, 2018 - PMID: 29681087 and Pohl et al, 2013 - PMID: 23851939). Other subjects reported were only evaluated as newborns(mostly)/infants [Paganini et al, 2017 - PMID: 28657137, Patil et al, 2018 - PMID: 29681087]. While the first report by Pohl et al identified a homozygous missense variant supported by functional studies [NM_006192.5:c.497G>T - p.(Gly166Val)] subsequent ones identified homozygosity for pLoF mutations [Patil et al: NM_006192.4:c.1173_1174insGCCCG / Paganini et al: NM_006192:c.1104C>A - p.(Cys368*)]. As discussed by Pohl et al: PAX1 encodes a transcription factor with critical role in pattern formation during embryogenesis. Study of the mouse Gly157Val (equivalent to human Gly166Val) Pax1 variant suggested reduced binding affinity (reduced transactivation of a regulatory sequence of the Nkx3-2 promoter) and hypofunctional nature of this variant. Mouse models seem to recapitulate features of the disorder (skeletal, immunodeficiency) while the role of Pax1 in hearing process was thought to be supported by early expression (P6) in mouse cochlea. Overall this gene can be considered for inclusion in the ID panel with amber/green rating. Sources: Literature, Radboud University Medical Center, Nijmegen |
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| Intellectual disability syndromic and non-syndromic v0.2750 | EXOC2 |
Konstantinos Varvagiannis gene: EXOC2 was added gene: EXOC2 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: EXOC2 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: EXOC2 were set to 32639540 Phenotypes for gene: EXOC2 were set to Global developmental delay; Intellectual disability; Abnormality of the face; Abnormality of brain morphology Penetrance for gene: EXOC2 were set to Complete Review for gene: EXOC2 was set to AMBER Added comment: Van Bergen et al (2020 - PMID: 32639540) report on 3 individuals from 2 families, harboring biallelic EXOC2 mutations. Clinical presentation included DD, ID (severe in 2 subjects from fam1, borderline intellectual functioning in fam2), dysmorphic features and brain abnormalities. Cerebellar anomalies were common to all with a molar tooth sign observed in one (1/3). Other findings limited to subjects from one family included acquired microcephaly, congenital contractures, spastic quadriplegia (each observed 2/3). Previous investigations were in all cases non-diagnostic. WES identified biallelic EXOC2 mutations in all affected individuals. EXOC2 encodes an exocyst subunit. The latter is an octameric complex, component of the membrane transport machinery, required for tethering and fusion of vesicles at the plasma membrane. As discussed ,vesicle transport is important for the development of brain and the function of neurons and glia. Exocyst function is also important for delivery of Arl13b to the primary cilium (biallelic ARL13B mutations cause Joubert syndrome 8) and ciliogenesis. Affected subjects from a broader consanguineous family (fam1) were homozygous for a truncating variant. Fibroblast studies revealed mRNA levels compatible with NMD (further restored in presence of CHX) as well as reduced protein levels. The female belonging to the second non-consanguineous family was found to harbor 2 missense variants in trans configuration. An exocytosis defect was demonstrated in fibroblasts from individuals belonging to both families. Ciliogenesis appeared to be normal, however Arl13b localization/recruitment to the cilia was reduced compared with control cells with the defect rescued upon exogenous expression of wt EXOC2. Mutations in other genes encoding components of the exocyst complex have been previously reported in individuals with relevant phenotypes (e.g. EXOC8 in a boy with features of Joubert s. or EXOC4 in nephrotic syndrome). The authors discuss on the essential role of EXOC2 based on model organism studies (e.g. impaired neuronal membrane traffic, failure of neuronal polarization and neuromuscular junction expansion seen in Drosophila Sec5 (EXOC2) null mutants). Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.2724 | MCM3AP | Zornitza Stark edited their review of gene: MCM3AP: Added comment: PMID: 32202298 - Woldegebriel et al 2020 - report a further two families, one in the Netherlands and one in Estonia, with probands with compound heterozygous variants in MCM3AP and a peripheral neuropathy with or without impaired intellectual development (MIM 618124) phenotype. The child from the Netherlands presented with severe hypotonia and intellectual disability. The two siblings from the Estonian family had severe generalized epilepsy and mild spastic diplegia. Functional studies using skin fibroblasts from these and other affected patients showed that disease variants result in depletion of GANP (encoded by MCM3AP) except when they alter critical residues in the Sac3 mRNA binding domain. GANP depletion was associated with more severe phenotypes compared with the Sac3 variants.; Changed publications: 32202298 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.2703 | GOLGA2 |
Elena Savva gene: GOLGA2 was added gene: GOLGA2 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: GOLGA2 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: GOLGA2 were set to PMID: 30237576; 26742501 Phenotypes for gene: GOLGA2 were set to Neuromuscular disorder Review for gene: GOLGA2 was set to AMBER Added comment: PMID: 30237576 - One 11 year old patient with a homozygous PTC. Patient had global dev delay, microcephaly, distal muscle weakness with joint contractures and elevated CK levels. Muscle biopsy showed dystrophin changes. MRI at 2 years old showed brain atrophy with thin corpus callosum and hypomyelination. No seizures or regression. PMID: 26742501 - One infant with a homozygous PTC. Patient had dev delay, seizures, microcephaly and muscular dystrophy. Zebrafish null model recapitulates the human phenotype with microcephaly and skeletal muscle disorganization. Summary: 2 patients Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.2627 | UGDH |
Konstantinos Varvagiannis gene: UGDH was added gene: UGDH was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: UGDH was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: UGDH were set to 32001716 Phenotypes for gene: UGDH were set to Epileptic encephalopathy, early infantile, 84 - MIM #618792 Penetrance for gene: UGDH were set to Complete Review for gene: UGDH was set to GREEN Added comment: Hengel et al (2020 - PMID: 32001716) report on 36 individuals with biallelic UGDH pathogenic variants. The phenotype corresponded overall to a developmental epileptic encephalopathy with hypotonia, feeding difficulties, severe global DD, moderate or commonly severe ID in all. Hypotonia and motor disorder (incl. spasticity, dystonia, ataxia, chorea, etc) often occurred prior to the onset of seizures. A single individual did not present seizures and 2 sibs had only seizures in the setting of fever. Affected subjects were tested by exome sequencing and UGDH variants were the only/best candidates for the phenotype following also segregation studies. Many were compound heterozygous or homozygous (~6 families were consanguineous) for missense variants and few were compound heterozygous for missense and pLoF variants. There were no individuals with biallelic pLoF variants identified. Parental/sib studies were all compatible with AR inheritance mode. UGDH encodes the enzyme UDP-glucose dehydrogenase which converts UDP-glucose to UDP-glucuronate, the latter being a critical component of the glycosaminoglycans, hyaluronan, chondroitin sulfate, and heparan sulfate [OMIM]. Patient fibroblast and biochemical assays suggested a LoF effect of variants leading to impairment of UGDH stability, oligomerization or enzymatic activity (decreased UGDH-catalyzed reduction of NAD+ to NADH / hyaluronic acid production which requires UDP-glucuronate). Attempts to model the disorder using an already developped zebrafish model (for a hypomorphic LoF allele) were unsuccessful as fish did not exhibit seizures spontaneously or upon induction with PTZ. Modelling of the disorder in vitro using patient-derived cerebral organoids demonstrated smaller organoids due to reduced number of proliferating neural progenitors. Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.2625 | YIF1B |
Konstantinos Varvagiannis gene: YIF1B was added gene: YIF1B was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: YIF1B was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: YIF1B were set to 32006098 Phenotypes for gene: YIF1B were set to Central hypotonia; Failure to thrive; Microcephaly; Global developmental delay; Intellectual disability; Seizures; Spasticity; Abnormality of movement Penetrance for gene: YIF1B were set to Complete Review for gene: YIF1B was set to GREEN Added comment: AlMuhaizea et al (2020 - PMID: 32006098) report on the phenotype of 6 individuals (from 5 families) with biallelic YIF1B truncating variants. Affected subjects presented hypotonia, failure to thrive, microcephaly (5/6), severe global DD and ID (as evident from best motor/language milestones achieved - Table S1) as well as features suggestive of a motor disorder (dystonia/spasticity/dyskinesia). Seizures were reported in 2 unrelated individuals (2/6). MRI abnormalities were observed in some with thin CC being a feature in 3. Variable initial investigations were performed including SNP CMA, MECP2, microcephaly / neurotransmitter disorders gene panel testing did not reveal P/LP variants. YIF1B variants were identified in 3 families within ROH. Following exome sequencing, affected individuals were found to be homozygous for truncating variants (4/5 families being consanguineous). The following 3 variants were identified (NM_001039672.2) : c.186dupT or p.Ala64fs / c.360_361insACAT or p.Gly121fs / c.598G>T or p.Glu200*. YIF1B encodes an intracellular transmembrane protein. It has been previously demonstrated that - similarly to other proteins of the Yip family being implicated in intracellular traffic between the Golgi - Yif1B is involved in the anterograde traffic pathway. Yif1B KO mice demonstrate a disorganized Golgi architecture in pyramidal hippocampal neurons (Alterio et al 2015 - PMID: 26077767). The rat ortholog interacts with serotonin receptor 1 (5-HT1AR) with colocalization of Yif1BB and 5-HT1AR in intermediate compartment vesicles and involvement of the former in intracellular trafficing/modulation of 5-HT1AR transport to dendrites (PMID cited: 18685031). Available mRNA and protein expression data (Protein Atlas) suggest that the gene is widely expressed in all tissues incl. neuronal cells. Immunochemistry data from the Human Brain Atlas also suggest that YIF1B is found in vesicles and localized to the Golgi apparatus. Immunohistochemistry in normal human brain tissue (cerebral cortex) demonstrated labeling of neuronal cells (Human Protein Atlas). Functional/network analysis of genes co-regulated with YIF1B based on available RNAseq data, suggest enrichement in in genes important for nervous system development and function. Please consider inclusion in other panels that may be relevant (e.g. microcephaly, etc). Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.2619 | CDC42BPB |
Konstantinos Varvagiannis gene: CDC42BPB was added gene: CDC42BPB was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: CDC42BPB was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: CDC42BPB were set to 32031333 Phenotypes for gene: CDC42BPB were set to Central hypotonia; Global developmental delay; Intellectual disability; Seizures; Autistic behavior; Behavioral abnormality Penetrance for gene: CDC42BPB were set to unknown Review for gene: CDC42BPB was set to GREEN Added comment: Chilton et al (2020 - PMID: 32031333) report on 14 individuals with missense and loss-of-function CDC42BPB variants. Features included hypotonia (8/11), DD (12/13 - the 14th was a fetus), ID (7/13), ASD (8/12), clinical seizures (in 3 - a 4th had abnormal EEG without seizures), behavioral abnormalities. Variable non-specific dysmorphic features were reported in some (sparse hair being the most frequent - 4/8). Additional features were observed in few (=<4) incl. cryptorchidism, ophthalmological issues, constipation, kidney abnormalities, micropenis, etc. All individuals had non-diagnostic prior genetic testing (incl. CMA, FMR1, MECP2, Angelman/Prader-Willi methylation studies, autism gene panel - suggesting relevance to the current panel) or metabolic testing. Variants were identified following clinical exome sequencing with Sanger confirmation. Most occurred as de novo events (11/14) while inheritance was not available for few (3/14). Missense variants did not display (particular) clustering. Almost all variants were absent from gnomAD and were predicted to be deleterious in silico (among others almost all had CADD scores >25). As the authors comment, CDC42BPB encodes myotonic dystrophy-related Cdc42-binding kinase β (MRCKβ) a serine/threonine protein kinase playing a role in regulation of cytoskeletal reorganization and cell migration in nonmuscle cells (through phosporylation of MLC2). Previous studies have demonstrated that it is ubiquitously expressed with prenatal brain expression. The gene appears to be intolerant to pLoF (pLI of 1) as well as to missense variants (Z-score of 3.66). CDC42BPB is a downstream effector of CDC42. Mutations of the latter cause Takenouchi-Kosaki syndrome with DD/ID and some further overlapping features (with CDC42BPB-associated phenotypes). Homozygous Cdc42bpb KO in mouse appears to be nonviable (MGI:2136459). Loss of gek in the eyes of Drosophila results in disrupted growth cone targeting to the lamina (gek is the fly CDC42BPB ortholog). Please consider inclusion with amber / green rating in the ID panel (>=4 relevant individuals / variants) and other panels (e.g. for epilepsy, ASD). Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.1972 | GAN | Zornitza Stark Marked gene: GAN as ready | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1972 | GAN | Zornitza Stark Gene: gan has been classified as Red List (Low Evidence). | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1972 | GAN | Zornitza Stark Phenotypes for gene: GAN were changed from to Giant axonal neuropathy-1, MIM# 256850 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1971 | GAN | Zornitza Stark Mode of inheritance for gene: GAN was changed from Unknown to BIALLELIC, autosomal or pseudoautosomal | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1970 | GAN | Zornitza Stark Classified gene: GAN as Red List (low evidence) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1970 | GAN | Zornitza Stark Gene: gan has been classified as Red List (Low Evidence). | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1969 | GAN | Zornitza Stark reviewed gene: GAN: Rating: RED; Mode of pathogenicity: None; Publications: ; Phenotypes: Giant axonal neuropathy-1, MIM# 256850; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1605 | MAPK8IP3 |
Alison Yeung gene: MAPK8IP3 was added gene: MAPK8IP3 was added to Intellectual disability syndromic and non-syndromic. Sources: Literature Mode of inheritance for gene: MAPK8IP3 was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: MAPK8IP3 were set to 30612693 Phenotypes for gene: MAPK8IP3 were set to Neurodevelopmental disorder with or without variable brain abnormalities OMIM# 605431 Review for gene: MAPK8IP3 was set to GREEN gene: MAPK8IP3 was marked as current diagnostic Added comment: >3 reported individuals and functional evidence in Caenorhabditis elegans Sources: Literature |
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| Intellectual disability syndromic and non-syndromic v0.1219 | SLC20A2 | Zornitza Stark Phenotypes for gene: SLC20A2 were changed from to Basal ganglia calcification, idiopathic, 1, MIM#213600 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.1216 | SLC20A2 | Zornitza Stark reviewed gene: SLC20A2: Rating: RED; Mode of pathogenicity: None; Publications: ; Phenotypes: Basal ganglia calcification, idiopathic, 1, MIM#213600; Mode of inheritance: MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.943 | PDGFB | Zornitza Stark Phenotypes for gene: PDGFB were changed from to Basal ganglia calcification, idiopathic, 5, MIM#615483 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.940 | PDGFB | Zornitza Stark reviewed gene: PDGFB: Rating: RED; Mode of pathogenicity: None; Publications: ; Phenotypes: Basal ganglia calcification, idiopathic, 5, MIM#615483; Mode of inheritance: MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Intellectual disability syndromic and non-syndromic v0.0 | GAN |
Zornitza Stark gene: GAN was added gene: GAN was added to Intellectual disability, syndromic and non-syndromic_GHQ. Sources: Expert Review Green,Genetic Health Queensland Mode of inheritance for gene: GAN was set to Unknown |
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