CYP1A1, CYP19, and GSTM1 polymorphisms increase the risk of endometriosis.

Objective: To investigate the possibility of genetic contribution of CYP1A1, CYP19, GSTM1, and GSTT1 polymorphisms to endometriosis.

Design: Genetic polymorphism analysis.

Setting: Case-control study.

Patient(s): A group of 275 women with sporadic endometriosis was compared with a group of 346 fertile, endometriosis-free women.

Intervention(s): Surgical, laparoscopic, and histological examination.

Main Outcome Measure(s): Blood specimens were obtained from endometriosis cases and controls. Polymerase chain reaction-based assays were performed for the determination of individual's genotype.

Result(s): The CYP19 VNTR, located in intron 4 (TTTA)(10) allele increases the risk for endometriosis development (odds ratio [OR], 4.99; 95% confidence interval [95% CI], 1.351 to 18.436). The combined genotype CYP1A1 wt/m1 or m1/m1 and GSTM1 null deletion adds to this risk (OR, 1.95; 95% CI, 1.266 to 2.995 and OR, 2.23; 95% CI, 0.631 to 7.906, respectively). In contrast, the CYP1A1 wt/wt genotype exhibits a protective effect, with a 38% reduction in the odds for endometriosis development (OR, 0.62; 95% CI, 0.440 to 0.883).

Conclusion(s): Our data suggest that CYP19 VNTR (TTTA)(10) allele as well as the combined genotype CYP1A1 m1 polymorphism and GSTM1 null deletion associate with the endometriosis phenotype, whereas the GSTT1 null deletion does not.