Association study of rs323344 in TEX15 with non-obstructive azoospermia in Iranian population

Abstract

Infertility is a global health issue that affected approximately 15% of couples across the world. Genetic and environmental factors have a significant role in the manifestation of male infertility. Genetic factors contribute to 15% - 30% of male infertility. Testis expressed 15 (TEX15) gene plays an important role in chromosome synapsis, DNA double-strand break repair, and meiotic recombination. DNA double-strand break repair is required during homologous chromosome pairing and chromosome synapsis. The TEX15 gene is essential for normal gametogenesis and maintenance of genome integrity. The present study was carried out to investigate the association of SNP rs323344 (p.Leu1720Val, c.5158 T>G) in the TEX15 gene with azoospermia male infertility among the Iranian population. To conduct this case-control study, a total of 100 Iranian men, including 50 infertile cases diagnosed with non-obstructive azoospermia and 50 fertile controls from 5 different ethnics, were recruited. SNP rs323344 was genotyped using the polymerase chain reaction-restriction fragment length (PCR-RFLP) method. Furthermore, a number of samples were sequenced by the Sanger sequencing method. Variants rs323344 in TEX15 showed the lack of statistically significant differences in genotype distributions between men diagnosed with azoospermia infertility and the fertile group in our studied samples in Iran. In general, our studied genome segment demonstrated a high degree of conservation and a low level of nucleotide variability. Our findings indicated that the SNP rs323344 and its neighboring nucleotides play no role in male infertility. This variant cannot be considered a biomarker for azoospermia in the Iranian population. Further studies with larger sample sizes and different ethnic backgrounds are needed to confirm the present findings.