Variants in BRWD3 associated with X-linked partial epilepsy without intellectual disability

Area of Science:

• Genetics
• Neurology
• Molecular Biology

Background:

• Idiopathic partial epilepsy (IPE) etiology is often unknown.
• Genetic factors are suspected in many IPE cases.
• Screening for disease-associated variants is crucial.

Purpose of the Study:

• To identify potential disease-associated variants in patients with idiopathic partial epilepsy (IPE).
• To investigate the role of the BRWD3 gene in IPE.
• To correlate BRWD3 variant genotypes and locations with phenotypic variations.

Main Methods:

• Whole exome sequencing in 320 IPE patients.
• Analysis of variant frequency and predicted molecular effects.
• Comparison of variant frequencies between patients and controls.

Main Results:

• Three novel BRWD3 variants identified in five IPE cases (four males, one female).
• Two missense variants (p.Thr279Ile, p.Ile1412Leu) and one intronic variant identified.
• Mutant BRWD3 alleles were significantly more frequent in IPE patients than controls.
• Missense variants in WD40 repeat and bromodomain were associated with epilepsy, unlike other destructive BRWD3 variants causing intellectual disability.

Conclusions:

• The BRWD3 gene is potentially associated with X-linked partial epilepsy.
• Specific BRWD3 variants may lead to epilepsy without intellectual disability.
• Genotype and variant location influence the phenotype of BRWD3-associated epilepsy.