A Novel Missense Mutation in TWNK Gene Causing Perrault Syndrome Type 5 in a Chinese Family and Review of the Literature

BACKGROUND: Perrault syndrome (PRLTS) is a rare autosomal recessive disorder characterized by sensorineural hearing loss in both sexes and ovarian dysfunction in females. In some cases, patients present with a diversity of neurological signs. Six genes are known to cause Perrault syndrome. CASE REPORT: We report an 11-year-old Chinese girl with delayed gonadal development, sensorineural hearing loss, and neurologic manifestations. Genetic etiology was identified by whole-exome sequencing and confirmed via Sanger sequencing. Compound heterozygous variants with one novel variant c.1752C>A (p.D584E) and one known pathogenic variant c.1172G>A (p.R391H) in TWNK were discovered in the child and inherited from her parents, respectively. CONCLUSION: The compound heterozygous variants c.1172G>A (p.R391H) and c.1752C>A (p.D584E) of the TWNK gene probably underlie PRLTS type 5 (PRLTS5). This study expands the mutation spectrum of TWNK pathogenicity in the PRLTS5 phenotype.