XRCC5 VNTR, XRCC6 -61C>G, and XRCC7 6721G>T Gene Polymorphisms Associated with Male Infertility Risk: Evidences from Case-Control and In Silico Studies.
ABSTRACT: We evaluate the association between genetic polymorphisms of XRCC5 VNTR, XRCC6 -61C>G, and XRCC7 6721G>T with male infertility susceptibility. A total of 392 men including 178 infertile males (102 idiopathic azoospermia and 76 severe oligozoospermia) and 214 healthy controls were recruited. XRCC6 -61C>G and XRCC7 6721G>T genotyping was performed by PCR-RFLP whereas XRCC5 VNTR was performed by PCR. The 2R allele and 2R allele carriers of XRCC5 VNTR polymorphism significantly decreased risk of male infertility. The mutant GG genotypes and carriers of the CG and GG genotypes of XRCC6 -61C>G showed increased risk for the male infertility. Furthermore, the G allele of the XRCC6 -61C>G was correlated with increased susceptibility to male infertility. Likewise, the T allele of the XRCC7 6721G>T polymorphism was associated with increased susceptibility to male infertility in azoospermia. In silico analysis predicted that the presence of tandem repeats in XRCC5 gene prompter can be sequence to bind to more nuclear factors. Also, rs2267437 (C>G) variant was located in a well-conserved region in XRCC6 promoter and this variation might lead to differential allelic expression. The XRCC7 6721G>T gene polymorphism occurred in an acceptor-splicing site, but this polymorphism has no severe modification on XRCC7 mRNA splicing. Our results indicate the association of XRCC5 VNTR, XRCC6 -61C>G, and XRCC7 6721G>T gene polymorphisms with male infertility in Iranian men.
Project description:<h4>Background</h4>Radio-adaptive response (RAR) is transient phenomena, where cells conditioned with a small dose (priming) of ionizing radiation shows significantly reduced DNA damage with a subsequent high challenging dose. The role of DNA double strand break repair gene polymorphism in RAR is not known. In the present study attempt was made to find out the influence of NHEJ repair gene polymorphisms [a VNTR; XRCC5 (3R/2R/1R/0R); two single nucleotide polymorphisms (SNPs); XRCC6 (C/G) and XRCC7 (G/T)] with DNA damage, repair and mRNA expression in human PBMCs in dose and adaptive response studies. Genomic DNA extracted from venous blood samples of 20 random healthy donors (16 adaptive and 4 non-adaptive) and genotyping of NHEJ repair genes was carried out using PCR amplified length polymorphism.<h4>Results</h4>The dose response study revealed significant positive correlation of genotypes at XRRC5 (3R/2R/1R/0R), XRCC6(C/G) and XRCC7 (G/T) with DNA damage. Donors having genotypes with 2R allele at XRCC5 showed significant positive correlation with mRNA expression level (0R/2R: r?=?0.846, P?=?0.034; 1R/2R: r?=?0.698, P?=?0.0001 and 2R/2R: r?=?0.831, P?=?0.0001) for dose response. Genotypes C/C and C/G of XRCC6 showed a significant positive correlation (P?=?0.0001), whereas, genotype T/T of XRCC7 showed significant negative correlation (r?=?-?0.376, P?=?0.041) with mRNA expression.<h4>Conclusion</h4>Interestingly, adaptive donors having C/G genotype of XRCC6 showed significantly higher (P?<?0.05) mRNA expression level in primed cells suggesting their role in RAR. In addition, NHEJ repair gene polymorphisms play crucial role with radio-sensitivity and RAR in human PBMCs.
Project description:A previous genome-wide association study in European men identified four single nucleotide polymorphism (SNP) loci associated with male infertility. Our aim was to replicate, if possible, the association of these SNPs with Japanese male infertility.We genotyped four SNPs (rs5911500, rs10246939, rs2059807, and rs11204546) in 517 Japanese patients with male infertility and 369 fertile controls using SNP-specific real-time polymerase chain reaction TaqMan assays. Subsequently, we divided patients with male infertility into azoospermia (n?=?417) and oligospermia subgroups (n?=?70).The four SNPs previously identified in European men showed no significant association with collective male infertility in our Japanese cohort. However, allele frequency analysis did indicate a significantly higher frequency of the rs11204546 C allele of the OR2W3 gene in the oligospermia subset of infertility patients compared with controls (p?=?0.0037; odds ratio?=?1.74; 95 % confidence interval, 1.21-2.53).Although this study was somewhat limited by overall sample size, the OR2W3 gene polymorphism rs11204546 was significantly associated with oligospermia in Japanese men, suggesting that OR2W3 might be involved in genetic susceptibility to Japanese male infertility as well as in European males.
Project description:To investigate the association of single nucleotide polymorphism 260 and 386 (SNP260 and SNP386) gene with male infertility, an electronic search was performed to identify case-control studies evaluating the relationship of SNP260 or SNP386 of deleted in azoospermia-like (DAZL) and male infertility. Review Manager 5 was used to process the meta-analysis and other statistical analysis. A total of 139 records were retrieved, of which 13 case-control studies with total 2715 patients and 1835 normozoospermic men were included. SNP260 was found not to play a functional role in male oligo/azoospermia either for Caucasians or for Asians. But for SNP386, models of allele (A/G), dominant (AA/AG + GG), co-dominant (AA/AG) and super-dominant (AA + GG/AG) had a strong correlation to spermatogenic failure with related odds ratio being 0.15 (95% confidence interval [95% CI] 0.07 to 0.34, P < 0.00001), 0.16 (95% CI 0.07 to 0.35, P < 0.00001), 0.15 (95% CI 0.06 to 0.33, P < 0.00001) and 0.15 (95% CI 0.06 to 0.33, P < 0.00001), respectively. Moreover, this correlation was only found in the Chinese Han population (decreasing around 85% risk of oligo/azoospermia infertility) and not found in India, Japan, and Caucasian countries. Our analysis demonstrated that SNP260 of DAZL did not contribute to oligo/azoospermia while SNP386 was correlated to male infertility. However, this correlation was only found in China with a country-specific and ethnicity-specific manner.
Project description:OBJECTIVE:To investigate a kallikrein-related peptidase 2 (KLK2) single nucleotide polymorphism (SNP) in relation to male infertility because of its role in semen processing. We investigated the genetic association of the KLK2+255G>A genotype with male infertility. METHODS:We genotyped the SNP site located in intron 1 (+255G>A, rs2664155) of KLK2 from 218 men with male infertility (cases) and 220 fertile males (controls). Pyrosequencing analysis was performed for the genotyping. RESULTS:The SNP of the KLK2 gene had a statistically significant association with male infertility (p<0.05). The odds ratio for the minor allele (+255A) in the pooled sample was 0.47 (95% confidence intervals, 0.26-0.85) for rs2664155. CONCLUSION:The relationship of KLK2 SNP to male infertility is statistically significant, especially within the non-azoospermia group. Further study is needed to understand the mechanisms associated with male infertility.
Project description:Infertility is the inability of a couple to conceive after one and a half years of unprotected sex. Male infertility, which accounts for almost half of infertility cases, is considered as a major problem all over the world. The aim of this study was to investigate the association of CYP1A1 polymorphisms with idiopathic non-obstructive azoospermia in a South Indian cohort.An experimental study was conducted with idiopathic nonobstructive azoospermia. A total of 120 infertile and 80 fertile samples were collected, and DNA was then extracted from all samples. The CYP1A1*2A polymorphism genotyping was carried out by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).The genotype distribution of CYP1A1*2A polymorphism showed significant difference between patients and controls. Moreover, the CC genotype was associated with decreased risk of idiopathic non-obstructive azoospermia in comparison with the TT and TC genotypes.The current experimental study identified that the CT genotype of CYP1A1*2A polymorphism may contribute to the pathogenesis of male infertility in the South Indian population.
Project description:BACHGROUND:IL-1α produced by Sertoli cells is considered to act as a growth factor for spermatogonia. In this study, we investigated the association of the C376A polymorphism in IL-1α with male infertility in men referring to the Kashan IVF Center. MATERIALS AND METHODS:In this case-control study, 2 ml of blood was collected from 230 fertile and 230 infertile men. After DNA extraction, the C376A variant was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In addition, the molecular effects of the C376A transversion were analysed using bioinformatics tools. RESULTS:A significant association was observed between the homozygous genotype CC with male infertility [odds ratio (OR)=1.97, 95% confidence interval (CI)=1.14-3.41, P=0.016)]. Carriers of C (AC+CC) showed a similar risk for male infertility (OR=1.78, 95% CI=1.06-2.99, P=0.030). Also, allelic analysis showed that the C allele is associated with male infertility (OR=1.43, 95% CI=1.09-1.88, P=0.011). In sub-group analysis, we found that the AC genotype is associated with asthenozoospermia (OR=2.38, 95% CI=1.03-5.53, P=0.043). In addition, carriers of C were at high risk for asthenozoospermia (OR=2.25, 95% CI=1.01-4.10, P=0.047). Also, C allele was significantly associated with oligozoospermia (OR=1.44, 95% CI=1.01-2.06, P=0.049) and non-obstructive azoospermia (OR=1.67, 95% CI =1.04-2.68, P=0.034). Finally, in silico analysis showed that the C376A polymorphism could alter splicing especially in the acceptor site. CONCLUSION:This is the preliminary report on the association of IL-1α C376A polymorphism with male infertility in the Kashan population. This association shows that the IL-1α gene may be a biomarker for male infertility, and therefore needs additional investigations in future studies to validate this.
Project description:This study aims to explore possible associations between polymorphisms of common SNP rs1136410 and rS1805405 in PARP1 gene and male infertility with spermatogenesis impairment.The polymorphic distributions of SNP rs1136410 and rS1805405 were investigated by polymerase chain reaction and restriction fragment length polymorphism analysis in a Chinese cohort including 371 infertile patients with idiopathic azoospermia or oligospermia and 231 controls.Significant differences in the frequencies of allele and genotype of SNP rs1136410 were observed between patients with oligospermia and controls. The allele C (46.3 % vs. 36.4 %, P?=?0.003) and genotype CC (22.6 % vs. 13.4 %, P?=?0.014) significantly increased, whereas genotype TT (30 % vs. 40.7 %, P?=?0.021) significantly decreased in patients with oligospermia compared with controls at this SNP locus.These results indicated that genotype CC of SNP rs1136410 may increase the risk of oligosoermia and genotype TT of rs1136410 may have some protective effect from oligospermia, suggesting that the polymorphism of SNP rs1136410 in PARP1 gene may modify the susceptibility to male infertility with oligospermia.
Project description:TSSK6 is a member of the testis-specific serine/threonine kinase family. Male Tssk6 knockout mice are infertile owing to spermatogenic impairment, including sperm count reduction, a decrease in motile sperm number and motility rates, and an increase in the number of sperms with abnormal morphology. We investigated the possible association between variations of the TSSK6 gene and spermatogenic impairment in humans. Mutation screening of TSSK6 was carried out in 519 patients with azoospermia (n = 273) or severe oligozoospermia (n = 246) and in 359 controls with normozoospermia by denaturing high-performance liquid chromatography and DNA sequencing. The frequencies of alleles and genotypes of gene polymorphism were compared between patients and controls. A novel triallelic polymorphism in TSSK6, c.822+126T>G/C, was identified. The frequencies of genotype TT and allele T were increased dramatically in infertile patients compared with controls, whereas genotype TG, allele G and allele C frequencies were significantly higher in controls than in patients. Further study revealed that the allele C frequency of controls was remarkably higher than that of patients with oligospermia. Our findings, for the first time, suggested an association of c.822+126T>G/C in TSSK6 with spermatogenic impairment in humans in which allele T may be a risk factor for male infertility, while alleles C and G may decrease susceptibility to male infertility.
Project description:PURPOSE:Recently, genome-wide association studies of a Hutterite population in the USA revealed that five single nucleotide polymorphisms (SNPs) with a significant association with sperm quality and/or function in ethnically diverse men from Chicago were significantly correlated with family size. Of these, three SNPs (rs7867029, rs7174015, and rs12870438) were found to be significantly associated with the risk of azoospermia and/or oligozoospermia in a Japanese population. In this study, we investigated whether the rs10966811 (located in an intergenic region between the TUSC1 and IZUMO3 genes) and rs10129954 (located in the DPF3 gene) SNPs, previously related to family size, are associated with male infertility. In addition, we performed association analysis between rs12348 in TUSC1 and rs2772579 in IZUMO3 and male infertility. METHODS:We genotyped 145 patients with infertility (including 83 patients with azoospermia and 62 with oligozoospermia) and 713 fertile controls by PCR-RFLP technique for polymorphism. Because rs10966811 has no restriction sites, the SNP rs12376894 with strong linkage disequilibrium was selected as an alternative to rs10966811. RESULTS:There was a statistically significant association between rs12376894 proxy SNP of rs10966811 and oligozoospermia. Also, a statistically significant association between rs10129954 and azoospermia, and oligozoospermia was observed. When we assessed the relationship between rs12348 in TUSC1 and rs2772579 in IZUMO3 and male infertility traits, we found that rs12348 in TUSC1 was significantly associated with azoospermia and oligozoospermia, but rs2772579 in IZUMO3 was not associated with male infertility. CONCLUSION:We found that the polymorphisms in TUSC1 and DPF3 displayed strong associations with male infertility.
Project description:Ku80 is a subunit of the Ku heterodimer that binds to DNA double-strand break ends as part of the non-homologous end joining (NHEJ) pathway. Ku80 is also involved in homologous recombination (HR) via its interaction with BRCA1. Ku80 is encoded by the XRCC5 gene that contains a variable number tandem repeat (VNTR) insertion in its promoter region. Different VNTR genotypes can alter XRCC5 expression and affect Ku80 production, thereby affecting NHEJ and HR pathways. VNTR polymorphism is associated with multiple types of sporadic cancer. In this study, we investigated its potential association with familial breast cancer at the germline level. Using PCR, PAGE, Sanger sequencing, and statistical analyses, we compared VNTR genotypes in the XRCC5 promoter between healthy individuals and three types of familial breast cancer cases: mutated BRCA1 (BRCA1 (+)), mutated BRCA2 (BRCA2 (+)), and wild-type BRCA1/BRCA2 (BRCAx). We observed significant differences of VNTR genotypes between control and BRCA1 (+) group (P?<?0.0001) and BRCA2 (+) group (P?=?0.0042) but not BRCAx group (P?=?0.2185), and the differences were significant between control and cancer-affected BRCA1 (+) cases (P?<?0.0001) and BRCA2 (+) cases (P?=?0.0092) but not cancer-affected BRCAx cases (P?=?0.4251). Further analysis indicated that 2R/2R (OR?=?1.94, 95%CI?=?1.26-2.95, P?=?0.0096) and 2R/1R (OR?=?1.58, 95%CI?=?1.11-2.26, P?=?0.0388) were associated with increased risk but 1R/1R (OR?=?0.55, 95%CI?=?0.35-0.84, P?=?0.0196) and 1R/0R (OR?=?0, 95%CI?=?0-0.29, P?=?0.0012) were associated with decreased risk in cancer-affected BRCA1 (+) group; 2R/1R (OR?=?1.94, 95%CI?=?1.14-3.32, P?=?0.0242) was associated with increased risk in cancer-affected BRCA2 (+) group. No correlation was observed for the altered risk between cancer-affected or -unaffected carriers and between different age of cancer diagnosis in cancer-affected carriers. The frequently observed VNTR association with in BRCA1 (+) and BRCA2 (+) breast cancer group indicates that VNTR polymorphism in the XRCC5 promoter is associated with altered risk of breast cancer in BRCA1 (+) and BRCA2 (+) carriers.