Correlation of Novel Single Nucleotide Polymorphisms of USP26, TEX15 and TNP2 Genes with Male Infertility in North West of Iran

BACKGROUND: Observational studies that inspected the association of USP26, TEX15, and TNP2 novel single nucleo- tide polymorphism (SNP) with odds of male infertility are sparse. Male infertility prevalence in Iran is reported more than global prevalence, while about 30-50% of infertile male have no distinct reason yet and they are considered as idiopathic male infertility. This study was conducted to investigate association of different SNPs of USP26, TEX15, and TNP2 genes with male infertility among the Iranian population. MATERIALS AND METHODS: In this population-based case-control study, 120 diagnosed idiopathic azoospermia or severe oligospermia infertile cases range of 25-45 years old, and 120 age-matched fertile controls were recruited. Overall, six different variants from three genes were genotyped including USP26 rs61741870, USP26 rs144039408, TEX15 rs323344, TEX15 rs61732458, TNP2 rs11640138 and TNP2 rs199536093 by using amplification-refractory mutation system polymerase chain reaction (ARMS-PCR) methods. RESULTS: Although there was no significant association of USP26 gene variants (rs61741870 and rs144039408) with men infertility, we found a significant association of TEX15 rs323344 T allele and odds of idiopathic azoospermia compared to recessive allele (odds ratio [OR]: 0.259, confidence intervals [CI]: 0.083-0.811). We determined signifi- cant associations of TEX15 rs61732458 AC and CA+AA with male infertility compared to normal homozygote (OR: 3.776, CI: 2.049-6.957, OR: 3.818, CI: 2.077-7.016, respectively). Significant association was seen among TNP2 rs199536093 GG genotype and idiopathic azoospermia compared to normal homozygote (OR: 0.348, CI: 0.129- 0.939). We also observed heterozygote overdominance in TEX15 rs61732458 and TNP2 rs199536093. CONCLUSION: We found novel polymorphisms related to male infertility among Iranian population. However, larger studies are needed to confirm the obtained results.