Genetic variants in the ETV5 gene in fertile and infertile men with nonobstructive azoospermia associated with Sertoli cell-only syndrome

Abstract

Objective: To assess the association between genetic variants in the ETV5 gene with nonobstructive azoospermia (NOA) associated with Sertoli cell-only (SCO) syndrome.

Design: Genetic association study.

Setting: University.

Patient(s): Australian men (65 SCO, 53 NOA, and 242 fertile men) and American men (86 SCO and 54 fertile men).

Intervention(s): Paraffin-embedded human testicular tissue was sectioned and processed for immunofluorescence. Direct DNA sequencing and polymerase chain reaction-based SNP detection were performed to define genetic variants in the ETV5 gene.

Main outcome measure(s): The localization of ETV5 in the human testis and the presence of ETV5 genetic variants in fertile and infertile men.

Result(s): ETV5 is localized to the cytoplasm and nucleus of Sertoli and germ cells in adult human testes. We identified six previously reported and six new genetic variants in the ETV5 gene. Of these, the allele frequency of the homozygous +48845 G>T (TT allele) variant was significantly higher in the SCO and NOA Australian men compared with fertile men.

Conclusion(s): The homozygous +48845 G>T (TT allele) variant confers a higher risk for male infertility associated with NOA and SCO in Australian men.