We first studied the biophysical and neurophysiological consequences of four mutations in the human Na+ channel gene SCN8A causing either mild (E1483K) or severe epilepsy (R1872W), or intellectual disability and autism without epilepsy (R1620L, A1622D).
One hundred twenty patients with MAE, 50 patients with absence epilepsy, and 37 patients with unselected epilepsies, intellectual disability (ID), and/or various movement disorders were screened for mutations in SLC2A1.
Familial glucose transporter type 1 (GLUT1) deficiency due to autosomal dominant inheritance of SLC2A1 mutations is associated with paroxysmal exertional dyskinesia; epilepsy and intellectual disability occur in some family members.
Clinical features of affected individuals with LGD variants in NAA15 include variable levels of intellectual disability, delayed speech and motor milestones, and autism spectrum disorder.
Our data confirm NDST1 mutations as a cause of autosomal recessive intellectual disability with a distinctive phenotype, and support an important function of NDST1 in human development.
Here, we report on a female patient with severe ID and autistic features carrying a de novo 0.4 Mb deletion containing six coding genes including KDM5C and IQSEC2.
In the ID-linked region at 12q24.22-12q24.31 19 out of 21 ID cases carried segmental CNV and 20 of 21 them displayed ROH segments with mean size lengths for ID cases 2512 kb (500-6,472 kb) and for healthy control 682 kb (531-986 kb), including the genes MED13L, HRK, FBXW8, TESC, CDK2AP1 and SBNO1.
Disruption of MED13L, encoding a component of the Mediator complex, is increasingly recognized as the cause of an intellectual disability syndrome with associated facial dysmorphism.
To access the impact of KDM5C variants on XLID, a cohort of 143 males with a family history of intellectual disability (ID) suggestive of X-linked inheritance were enrolled.
Using a positional cloning approach, we isolated a novel gene, PROSIT240 (also termed THRAP2), that is interrupted in a patient with a chromosomal translocation and who displays TGA and mental retardation.
Mutations in <i>KDM5C</i> cause Mental Retardation, X-linked, Syndromic, Claes-Jensen type (MRXSCJ, OMIM #300534) and are one of the most common causes of X-linked ID.
Recently, a new syndrome caused by MED13L deleterious variants has been described, which shows similar clinical manifestations including intellectual disability, hypotonia, and other congenital anomalies.
Mutation analysis of the JARID1C gene was conducted in the following cohorts: probands from 23 XLMR families linked to Xp11.2, 92 males with mental retardation and short stature, and 172 probands from small XLMR families with no linkage information.
In this study, we describe clinical and genetic findings of a Brazilian family co-segregating a novel nonsense mutation (c.2172C>A) in exon 15 of KDM5C gene with the intellectual disability phenotype.