ABSTRACT
<p><b>OBJECTIVE</b>The Ala499Val (C > T) and Lys939Gln (A > C) of the XPC gene are two potentially functional nonsynonymous polymorphisms, which affect the rate of DNA repair and might change XPC production and activity. This study aimed to explore the distribution of these two polymorphisms in the Chinese Han population and their relationship with male infertility.</p><p><b>METHODS</b>We genotyped the two polymorphisms of the XPC gene by the PCR-restriction fragment length polymorphism (PCR-RFLP) method in 318 infertile patients and 228 fertile male controls, detected the frequency of the alleles, and analyzed both the individual and the joint contribution of the two polymorphisms to male infertility.</p><p><b>RESULTS</b>For the Ala499Val (C > T) polymorphism, the frequencies of the CC, CT, and TT genotypes were significantly different in distribution between the patients and the controls (P = 0.020). Males with the TT genotype had a lower risk of male infertility than those with the CC genotype (adjusted OR = 0.49, 95% CI: 0.23-0.88), and even lower than those with both CC and CT genotypes (adjusted OR = 0.39, 95% CI: 0.22-0.71). The Lys939Gln (A > C) polymorphism was not related with male infertility. The combined genotype analysis showed that the individuals with 1-4 risk alleles had a significantly higher risk of male infertility (adjusted OR = 2.75, 95% CI = 1.50-5.04) than those with 0 risk allele.</p><p><b>CONCLUSION</b>The Ala499Val (C > T) polymorphism of the XPC gene is correlated with male infertility and may be a potential genetic risk factor for male infertility in the Chinese Han population.</p>
Subject(s)
Adult , Humans , Male , Alleles , Asian People , Genetics , Case-Control Studies , DNA Repair , DNA-Binding Proteins , Genetics , Gene Frequency , Genetic Predisposition to Disease , Genotype , Infertility, Male , Genetics , Polymorphism, Genetic , Risk FactorsABSTRACT
<p><b>AIM</b>To assess the possible role of genetic polymorphisms in DNA repair gene XRCC1 (X-ray repair cross-complementing group 1) during spermatogenesis by investigating the associations of one promoter polymorphism (T-77C) and two exonic polymorphisms (Arg194Trp and Arg399Gln) in XRCC1 gene with risk of idiopathic azoospermia in a Chinese population.</p><p><b>METHODS</b>The genotype and allele frequencies of three observed polymorphisms were examined by polymerase chain reaction-restriction fragment length polymorphism based on a Chinese population consisting of 171 idiopathic azoospermia subjects and 247 normal-spermatogenesis controls.</p><p><b>RESULTS</b>In our study, all the observed genotype frequencies were in agreement with Hardy-Weinberg equilibrium. The 399A (GA+AA) allele frequency for idiopathic azoospermia subjects and controls was 0.216 and 0.269, respectively. Compared with GG genotype, the AA genotype of Arg399Gln showed a significant association with a decreased risk of idiopathic azoospermia (odds ratio = 0.315; 95% confidence interval = 0.12-0.86). However, no significant differences were found between the cases and controls for T-77C and Arg194Trp polymorphisms. The major haplotypes of XRCC1 gene were TCG, TTG and TCA, whereas no haplotypes appeared to be significantly associated with idiopathic azoospermia based on the cutoff of P < 0.05.</p><p><b>CONCLUSION</b>In a selected Chinese population, AA genotype of Arg399Gln appears to contribute to a decreased risk of idiopathic azoospermia, while we have not any evidence of involvement of XRCC1 T-77C and Arg194Trp polymorphisms in idiopathic azoospermia.</p>