Autism
Gene: MARK2
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: LiteratureCreated: 7 Nov 2024, 1:32 a.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Neurodevelopmental disorder MONDO:0700092
Publications
Gene: mark2 has been classified as Green List (High Evidence).
Gene: mark2 has been classified as Green List (High Evidence).
gene: MARK2 was added gene: MARK2 was added to Autism. 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