This case report expands the phenotypic spectrum of SCN2A mutations by describing a novel variant causing ASD without comorbid epilepsy.
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. 4023₄077del (p. Val1343Alafs*17). This case enriches the ASD phenotype spectrum related to the SCN2A, especially providing a clinical example without comorbid epilepsy.
Gao et al. (Wed,) studied this question.