Identification of novel variants and candidate genes in women with 46,XX complete gonadal dysgenesis

Abstract

Abstract Background 46,XX complete gonadal dysgenesis (46,XX-CGD) is a rare disorder of sexual development (DSD) characterized by primary amenorrhea and a lack of spontaneous pubertal development in individuals with a 46,XX karyotype despite the presence of female internal and external genitalia due to failure of bilateral ovarian development. The condition is genetically heterogeneous, and in most cases, its etiology is unknown. Determining the genetic cause would provide insights into potential targets for genetic diagnosis and counseling. Methods To clarify the molecular mechanisms of 46,XX complete gonadal dysgenesis in the population of China, whole-exome sequencing (WES) was performed on DNA samples from patients with 46,XX-CGD. In silico analysis was conducted to predict the pathogenicity of the variants. Results We recruited 20 patients with 46,XX-CGD and identified 8 variants in 6 genes, including three homozygous variants in MCM9, POF1B, and PSMC3IP; compound heterozygous variants in TWNK; and three heterozygous variants in TP63 and INSRR, from 7 patients. These variants included 3 recurrent variants and 5 novel variants. Conclusions This study identified several novel variants, broadening the variant spectrum of 46,XX-CGD. 46,XX-CGD is a genetically heterogeneous condition, and WES is a powerful tool for determining its genetic etiology. The results of this study will aid researchers and clinicians in genetic counseling and suggest that WES is valuable for detecting 46,XX-CGD, which may lead to early interventions for patients.

Keywords

• DSD
• 46,XX-CGD
• Pathogenic variants
• WES
• Genetic etiology