The Association of GSTM1 and GSTT1 Null Polymorphisms with Endometriosis in a Korean Population

Objective: To explore the association of the phase II glutathione S-transferase mu (GSTM1), theta (GSTT1) gene null polymorphisms with endometriosis in a Korean population. Methods: One hundred forty eight women with surgically diagnosed endometriosis of stage I-IV were recruited. And 130 patients with no evidence of endometriosis by laparoscopy or laparotomy served as controls. Genomic DNA was extracted from peripheral blood and analyzed for GSTM1, GSTT1 null polymorphisms. Results: GSTM1 null genotype (GSTM1 0/0) was found more frequently in patients with endometriosis than in controls (61.5% in endometriosis vs. 49.2% in control, p=0.040). And the association was found only in moderate to severe endometriosis (stage III IV) (63.7% vs. 49.2%, p=0.027: odds ratio: 1.812), not in minimal or mild endometriosis (p=0.395). There was no significant difference between endometriosis patients and controls in the frequency of the GSTT1 null genotype (51.4% vs. 54.6%, p>0.1). Conclusion: These results suggest that GSTM1 null genotype is associated with the risk of endometriosis but GSTT1 null genotype is not in the Korean population.