A Novel HECW2 Variant (c.4354G>A; p. Gly1452Ser) in a Chinese Patient with Developmental Delay, Neurodevelopmental Delay, and Hypotonia

INTRODUCTION: Neurodevelopmental disorders (NDDs) due to the HECW2 (MIM:617245), the pathogenic variant, are extremely rare. HECW2-related disorder has been established through the identification of de novo variants in HECW2 gene in patients with NDDs with hypotonia, seizures, and absent language. CASE PRESENTATION: In this study, the clinical and genetic features of a Chinese girl with neurodevelopmental delay, developmental language disorder, and hypotonia are described. Trio whole exome sequencing revealed a novel likely pathogenic variant in HECW2 (exon26: c.4354G>A; p. Gly1452Ser) in the patient, while the variant was absent in her parents with Sanger sequencing. CONCLUSION: Our objective was to identify the potential site of HECW2, combined with the literature review, to find the correlation between clinical phenotype and genotype.