The HECW2 gene encodes a HECT (homologous to E6-AP carboxy terminus)-type E3 ubiquitin ligase that plays a critical role in neurodevelopment. Pathogenic variants in HECW2 are associated with a neurodevelopmental disorder characterized by hypotonia, seizures, and absent language (NDHSAL; OMIM #617268), typically inherited in an autosomal dominant pattern. However, recent evidence suggests that some variants in HECW2 gene may cause the disease with autosomal recessive inheritance.