The association between TNP2 gene polymorphisms and Iranian infertile men with varicocele: A case-control study

Polymorphisms and expression levels of TNP2, SYCP3, and AZFa genes in patients with azoospermia

OBJECTIVE

Azoospermia (the total absence of sperm in the ejaculate) affects approximately 10% of infertile males. Despite diagnostic advances, azoospermia remains the most challenging issue associated with infertility treatment. Our study evaluated transition nuclear protein 2 (TNP2) and synaptonemal complex protein 3 (SYCP3) polymorphisms, azoospermia factor a (AZFa) microdeletion, and gene expression levels in 100 patients with azoospermia.

METHODS

We investigated a TNP2 single-nucleotide polymorphism through polymerase chain reaction (PCR) restriction fragment length polymorphism analysis using a particular endonuclease. An allele-specific PCR assay for SYCP3 was performed utilizing two forward primers and a common reverse primer in two PCR reactions. Based on the European Academy of Andrology guidelines, AZFa microdeletions were evaluated by multiplex PCR. TNP2, SYCP3, and the AZFa region main gene (DEAD-box helicase 3 and Y-linked [DDX3Y]) expression levels were assessed via quantitative PCR, and receiver operating characteristic curve analysis was used to determine the diagnostic capability of these genes.

RESULTS

The TNP2 genotyping and allelic frequency in infertile males did not differ significantly from fertile volunteers. In participants with azoospermia, the allelic frequency of the SYCP3 mutant allele (C allele) was significantly altered. Deletion of sY84 and sY86 was discovered in patients with azoospermia and oligozoospermia. Moreover, SYCP3 and DDX3Y showed decreased expression levels in the azoospermia group, and they exhibited potential as biomarkers for diagnosing azoospermia (area under the curve, 0.722 and 0.720, respectively).

CONCLUSION

These results suggest that reduced SYCP3 and DDX3Y mRNA expression profiles in testicular tissue are associated with a higher likelihood of retrieving spermatozoa in individuals with azoospermia. The homozygous genotype TT of the SYCP3 polymorphism was significantly associated with azoospermia.

Correlation of Novel Single Nucleotide Polymorphisms ofUSP26, 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 nucleotide 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 significant 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.

Search for Associations of FSHR, INHA, INHAB, PRL, TNP2 and SPEF2 Genes Polymorphisms with Semen Quality in Russian Holstein Bulls (Pilot Study)

The aim of the study was to search for new mutations in the previously studied gene loci of follicle-stimulating hormone receptor (FSHR), inhibin α (INHA), inhibin β A (INHAB), prolactin (PRL), transition protein 2 (TNP2), and sperm flagella 2 (SPEF2) by sequencing, as well as the search for associations of previously identified mutations at these loci with fresh semen quality in Russian Holstein bulls. Phenotypic data from 189 bulls was collected. Data was analyzed for most bulls for three years of semen collection. The maximum value of each semen quality indicator (doublet ejaculate volume, sperm concentration, progressive motility and total number of spermatozoa) were selected. SNPs were identified in the FSHR, INHA, INHAB, TNP2, SPEF2 genes. The PRL gene did not have polymorphism. Significant (p < 0.05) associations of polymorphisms in the FSHR gene with double ejaculate volume, concentration and total number of spermatozoa were identified. Polymorphism in the INHA gene was significantly associated (p < 0.05) with sperm concentration. Polymorphism in the INHAB gene was significantly associated (p < 0.05) with doublet ejaculate volume and total number of spermatozoa. Polymorphisms in the TNP2 and SPEF2 genes did not have significant associations with semen quality. The SNPs studied in our pilot work may be considered as candidate genetic markers in the selection of bulls.