Genotype and phenotype analysis of epilepsy caused by ADGRV1 mutations in Chinese children

Objective: To investigate the genotype and phenotype of epilepsy caused by ADGRV1 variants in Chinese children.

Methods: A total of 625 patients with epilepsy who had undergone whole-exon gene sequencing or epilepsy and related paroxysmal disease gene panel sequencing were recruited. Variants were evaluated for susceptibility pathogenicity based on their frequency in the Genome Aggregation Database (≤ 0.001). We used six algorithms (sorting intolerant from tolerant (SIFT), PolyPhen-2, Mutation Taster, CADD, REVEL and Splice AI) that predicted that the ADGRV1 variant would have a harmful impact on the function of genes and gene products. We retrospectively reviewed the clinical information of patients with susceptible pathogenic ADGRV1 variants. The relationship between the genotype and phenotype was also analyzed.

Results: Eighteen patients with epilepsy were found to have likely pathogenic variants in ADGRV1. The rate of ADGRV1 variants in patients with epilepsy in this cohort was 2.88%. A total of 19 ADGRV1 variants were found, of which 13 were novel and 6 had been previously reported. Eleven out of the 18 children (61.1%) had febrile and afebrile seizures (FS and AS), two children had only FS, one child had infantile spasms, and the other four children had only AS that occurred during sleep (Rolandic epilepsy or atypical Rolandic epilepsy).

Significance: Our study showed a statistically significant association between ADGRV1 variants and FS and AS (p < 0.05), supporting the hypothesis that ADGRV1 is a susceptibility gene for Rolandic epilepsy and infantile spasms. Most epilepsy cases caused by ADGRV1 variants have a good prognosis.