A novel heterozygous ERCC6 variant identified in a Chinese family with non-syndromic primary ovarian insufficiency.

BACKGROUND

Premature ovarian insufficiency (POI) is a clinical syndrome occurring in women before 40 with decreased ovarian function. Up to 25% of POI cases result from genetic factors that remain largely unknown. The Excision repair cross-complementing, group 6 (ERCC6) variant has been found to cause POI, which is hardly ever diagnosed in adolescents.

METHODS

Whole-exome sequencing was performed on a 19-year-old proband with non-syndromic POI and her parents. Sanger sequencing was used to confirm the identified variant. The effect of the variant on the protein was analyzed in silico and Swiss-MODEL.

RESULTS

A novel heterozygous missense variant, c.2444G > A (p. GLy815Asp) of ERCC6 was identified in the proband who inherited the variant from her father. The variant was confirmed in another POI patient from the pedigree and was absent in the proband's mother and sister who presented normally. In silico analysis predicted this variant was deleterious. Swiss-Model revealed that the mutant amino acid formed multiple H-bonds with adjacent residues, which may lead to a dysfunction of ERCC6 protein.

CONCLUSION

We firstly diagnosed an adolescent POI case associated with a novel heterozygous ERCC6 variant. The results expanded the variants spectrum of ERCC6 and provided guidance for POI diagnosis and genetic counselling.