Mendeliome
Gene: TUBA4A Green List (high evidence)Green List (high evidence)
New papers reporting biallelic and monoallelic variants associated with OZEMA:
i) PMID: 39209701- Patients 3 and 4 from unrelated families with primary infertility experiencing recurrent preimplantation embryo development arrest (RPEA) carried homozygous frameshift deletion variant p.Tyr440Ter and missense variant p.Arg339Cys respectively. Transfection studies showed that caused both variants caused a significant decrease in the abundance of encoded proteins and abnormal cytoplasmic localisation manifested as localised protein aggregation. Differentially abundant transcripts in arrested embryos carrying the missense TUBA4A variant exhibited a trend of upregulation and were highly enriched in the mRNA metabolic process, and some key genes involved in degradation, such as MOS and PABPN1L have been shown to be significantly downregulated.
ii) PMID: 37024973 - Three unrelated infertile females with similar phenotypes of embryonic arrest carrying different de novo heterozygous missense variants (pE77K, pL286P, p.C347K). Functional study showed that all the three mutant proteins caused severe microtubule destabilization. They also identified additional nine sporadic cases (seven were with phenotype of early embryonic arrest and two with phenotype of oocyte maturation arrest) with eight different heterozygous missense TUBA4A variants. Functional study showed that six out of the eight variants (R215H, R229C, A273V, E284K, A314V, and R373H) were incorporated in microtubules with a more severely abnormal appearance. Microinjection of TUBA4A mutant cRNAs (8 out of 11 variants) significantly reduced the rate of first polar body extrusion to 24.5–66.3% and microinjection of TUBA4A mutant cRNAs (6 out of 11 variants) also resulted in embryonic development arrest and reduced the rate of blastocyst formation to 51.0–65.0%.
iii) PMID: 39872894- Three isolated infertile female with zygotic arrest carrying heterozygous missense variants (P1- de novo p.E284K, P2- p.E284G, P3- p.E284K). Injection of mRNA encoding E284G and E284K mutants into mouse GV oocytes showed highly disrupted spindle morphology and apparent chromosome misalignment, only about 30% E284G- and E284K-injected oocytes completed meiosis I.Created: 10 Jun 2025, 4 p.m. | Last Modified: 10 Jun 2025, 4 p.m.
Panel Version: 1.2648
Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes
Oocyte/zygote/embryo maturation arrest 23, MIM# 621231
Green List (high evidence)
New association with ataxia with/without spasticity. The gene has also been implicated in MND, dementia, and to a lesser degree myopathy. The disease spectrum is similar to multisystem proteinopathy.
PMID: 38884572 - Multicentre cohort of 12 patients from 11 unrelated families presenting with ataxia age of onset 2-60 yrs (9 different missense variants). Spasticity was present in 7/12, 58.3%, cognitive decline in 4/12, 33,3%, and amyotrophy or upper limb muscular weakness in 2/12, 16.6%. 2 patients with p.Pro173Arg also had learning disabilities. 5 cases were confirmed de novo for the variants. Enrichment of rare missense in an ataxia cohort from UK 100k genomes - 6/1103 cases vs 2/20,904 controls, OR = 57.0847 [10.2- 576.7], p = 4.02e-7. Cultured fibroblasts from 3 patients harbouring distinct TUBA4A missense showed significant alterations in microtubule organisation and dynamics, suggestive of a dominant negative mechanism of disease.
PMID: 37418012 - 2 Italian spastic ataxia families with p.Glu415Lys, one family segregating the variant in 11 affected individuals and one de novo.Created: 3 Jul 2024, 8:21 a.m. | Last Modified: 3 Jul 2024, 8:21 a.m.
Panel Version: 1.1860
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Hereditary ataxia MONDO:0100309, TUBA4A-related
Publications
I don't know
One novel TUBA4A variant in two unrelated Chinese patients with sporadic congenital myopathy.
Identified candidate genes using laser capture micro dissection, proteomics, WES, clinical data, myopathological changes, electrophysiological exams and thigh muscle MRIs.
The variant is de novo in both patients, c.679C>T, p.(Leu227Phe). The prominent myopathological changes in both patients were muscle fibres with focal myofibrillar disorganisation and rimmed vacuoles. Immunofluorescence showed ubiqution-positive TUBA4A protein aggregates in the muscle fibres with rimmed vacuoles. Overexpression of Leu227Phe resulted in cytoplasmic aggregates which colocalised with ubiquitin in cellular model.
Patient 1 is 14yo and had delayed motor development milestones since infancy. Myopathic face, high-arched palate, waddling gait, winged scapula and muscle weakness in four limbs with lower extremities and proximal muscle more severely affected. Follow up at 14yo showed slight improvement in motor function compared with 3yo.
Patient 2 is 6yo and presented with motor retardation since birth. At 3yo, presented with mild ptosis and ophthalmoparesis, high-arched palate and muscle weakness involving both proximal and distal in all limbs.
No likely pathogenic variants in 116 other protein-encoding genes. Variants confirmed by Sanger sequencing and absent from gnomAD. ACMG predicts likely pathogenic classification.
Sources: LiteratureCreated: 7 Mar 2024, 12:29 a.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Congenital myopathy MONDO:0019952
Publications
Phenotypes for gene: TUBA4A were changed from Congenital myopathy 26, MIM# 621225; Hereditary ataxia MONDO:0100309, TUBA4A-related to Congenital myopathy 26, MIM# 621225; Hereditary ataxia MONDO:0100309, TUBA4A-related; Oocyte/zygote/embryo maturation arrest 23, MIM# 621231
Phenotypes for gene: TUBA4A were changed from Congenital myopathy MONDO:0019952 to Congenital myopathy 26, MIM# 621225; Hereditary ataxia MONDO:0100309, TUBA4A-related
Gene: tuba4a has been classified as Green List (High Evidence).
Gene: tuba4a has been classified as Amber List (Moderate Evidence).
Gene: tuba4a has been classified as Amber List (Moderate Evidence).
gene: TUBA4A was added gene: TUBA4A was added to Mendeliome. Sources: Literature Mode of inheritance for gene: TUBA4A was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: TUBA4A were set to PMID: 38413182 Phenotypes for gene: TUBA4A were set to Congenital myopathy MONDO:0019952 Review for gene: TUBA4A was set to AMBER
If promoting or demoting a gene, please provide comments to justify a decision to move it.
Genes included in a Genomics England gene panel for a rare disease category (green list) should fit the criteria A-E outlined below.
These guidelines were developed as a combination of the ClinGen DEFINITIVE evidence for a causal role of the gene in the disease(a), and the Developmental Disorder Genotype-Phenotype (DDG2P) CONFIRMED DD Gene evidence level(b) (please see the original references provided below for full details). These help provide a guideline for expert reviewers when assessing whether a gene should be on the green or the red list of a panel.
A. There are plausible disease-causing mutations(i) within, affecting or encompassing an interpretable functional region(ii) of this gene identified in multiple (>3) unrelated cases/families with the phenotype(iii).
OR
B. There are plausible disease-causing mutations(i) within, affecting or encompassing cis-regulatory elements convincingly affecting the expression of a single gene identified in multiple (>3) unrelated cases/families with the phenotype(iii).
OR
C. As definitions A or B but in 2 or 3 unrelated cases/families with the phenotype, with the addition of convincing bioinformatic or functional evidence of causation e.g. known inborn error of metabolism with mutation in orthologous gene which is known to have the relevant deficient enzymatic activity in other species; existence of an animal model which recapitulates the human phenotype.
AND
D. Evidence indicates that disease-causing mutations follow a Mendelian pattern of causation appropriate for reporting in a diagnostic setting(iv).
AND
E. No convincing evidence exists or has emerged that contradicts the role of the gene in the specified phenotype.
(i)Plausible disease-causing mutations: Recurrent de novo mutations convincingly affecting gene function. Rare, fully-penetrant mutations - relevant genotype never, or very rarely, seen in controls. (ii) Interpretable functional region: ORF in protein coding genes miRNA stem or loop. (iii) Phenotype: the rare disease category, as described in the eligibility statement. (iv) Intermediate penetrance genes should not be included.
It’s assumed that loss-of-function variants in this gene can cause the disease/phenotype unless an exception to this rule is known. We would like to collect information regarding exceptions. An example exception is the PCSK9 gene, where loss-of-function variants are not relevant for a hypercholesterolemia phenotype as they are associated with increased LDL-cholesterol uptake via LDLR (PMID: 25911073).
If a curated set of known-pathogenic variants is available for this gene-phenotype, please contact us at panelapp@genomicsengland.co.uk
We classify loss-of-function variants as those with the following Sequence Ontology (SO) terms:
Term descriptions can be found on the PanelApp homepage and Ensembl.
If you are submitting this evaluation on behalf of a clinical laboratory please indicate whether you report variants in this gene as part of your current diagnostic practice by checking the box
Standardised terms were used to represent the gene-disease mode of inheritance, and were mapped to commonly used terms from the different sources. Below each of the terms is described, along with the equivalent commonly-used terms.
A variant on one allele of this gene can cause the disease, and imprinting has not been implicated.
A variant on the paternally-inherited allele of this gene can cause the disease, if the alternate allele is imprinted (function muted).
A variant on the maternally-inherited allele of this gene can cause the disease, if the alternate allele is imprinted (function muted).
A variant on one allele of this gene can cause the disease. This is the default used for autosomal dominant mode of inheritance where no knowledge of the imprinting status of the gene required to cause the disease is known. Mapped to the following commonly used terms from different sources: autosomal dominant, dominant, AD, DOMINANT.
A variant on both alleles of this gene is required to cause the disease. Mapped to the following commonly used terms from different sources: autosomal recessive, recessive, AR, RECESSIVE.
The disease can be caused by a variant on one or both alleles of this gene. Mapped to the following commonly used terms from different sources: autosomal recessive or autosomal dominant, recessive or dominant, AR/AD, AD/AR, DOMINANT/RECESSIVE, RECESSIVE/DOMINANT.
A variant on one allele of this gene can cause the disease, however a variant on both alleles of this gene can result in a more severe form of the disease/phenotype.
A variant in this gene can cause the disease in males as they have one X-chromosome allele, whereas a variant on both X-chromosome alleles is required to cause the disease in females. Mapped to the following commonly used term from different sources: X-linked recessive.
A variant in this gene can cause the disease in males as they have one X-chromosome allele. A variant on one allele of this gene may also cause the disease in females, though the disease/phenotype may be less severe and may have a later-onset than is seen in males. X-linked inactivation and mosaicism in different tissues complicate whether a female presents with the disease, and can change over their lifetime. This term is the default setting used for X-linked genes, where it is not known definitately whether females require a variant on each allele of this gene in order to be affected. Mapped to the following commonly used terms from different sources: X-linked dominant, x-linked, X-LINKED, X-linked.
The gene is in the mitochondrial genome and variants within this can cause this disease, maternally inherited. Mapped to the following commonly used term from different sources: Mitochondrial.
Mapped to the following commonly used terms from different sources: Unknown, NA, information not provided.
For example, if the mode of inheritance is digenic, please indicate this in the comments and which other gene is involved.