Autism Spectrum Disorder Caused by a Novel De Novo SCN2A Mutation: A Case Report

Autism spectrum disorder (ASD) exhibits significant genetic heterogeneity, and a large number of risk genes may eventually converge on a limited number of common pathways. Among them, SCN2A, which encodes the Nav1.2α subunit of the voltage-gated sodium channel, is one of the important risk genes. This article reports a case of ASD caused by a novel mutation in SCN2A. The patient is a 6-year-old female, with the main clinical manifestations being language development delay and social communication disorders, but without epilepsy. Whole-exome sequencing revealed that she carried a heterozygous variant in the SCN2A c.4023_4077del (p.Val1343Alafs*17). This case enriches the ASD phenotype spectrum related to the SCN2A, especially providing a clinical example without comorbid epilepsy.