Polymorphic variants of CYP17 and CYP19A and risk of infertility in endometriosis

OBJECTIVE: Endometriosis is recognized as an estrogen-dependent disease. There are conflicting data demonstrating single nuclear polymorphisms (SNPs) of CYP17 and CYP19 steroidogenic genes as related to endometriosis risk. We assessed the CYP17 5'-untranslated region -34 A/G (rs743572) and CYP19 Ex10 + C1558T (rs10046) SNPs in stage I-II endometriosis. DESIGN: Case-control study. SETTING: Division of reproduction at a university department in Poland. POPULATION: A total of 115 women with diagnosed stage I-II endometriosis according to the revised American Society for Reproductive Medicine (rASRM) classification and 197 fertile women as controls. METHODS: The SNPs CYP17 -34 A/G and CYP19 Ex10 + C1558T were identified by high-resolution melting curve analysis. MAIN OUTCOME MEASURES: Genotype prevalence and odds ratio for recessive and dominant genetic model for CYP17 and CYP19 SNPs. RESULTS: We observed a significantly increased CYP17 GG and GA genotype frequency in women diagnosed with rASRM stage I-II endometriosis compared with fertile women (OR = 2.4; 95% CI 1.4-4.2, p = 0.002). We also found a significantly increased CYP17 G allele frequency in cases compared with controls (OR = 1.6; 95% CI 1.2-2.2, p = 0.004). There were no significant differences in the distribution of the CYP17 GG genotype and CYP19 Ex10 + C1558T polymorphism between women diagnosed with rASRM stage I-II endometriosis and controls. CONCLUSION: The CYP17 -34 G variant, previously associated with increased 17β-estradiol production, displayed a contribution to stage I-II endometriosis in women from a Polish population. Increased 17β-estradiol concentration in carriers of the CYP17 -34 G variant might contribute to endometriosis and associated pathological processes.