Objective: To evaluate the interaction of glutathione-S-transferase (GST) gene polymorphisms and smoking as a risk factor for endometriosis.
Study design: The study group consisted of 150 women who were diagnosed by means of surgery and histopathology as having endometriosis. The control group consisted of 150 women who displayed no evidence of endometriosis during exploratory laparotomy or laparoscopy. We assessed the interaction of smoking and GSTM1 and GSTT1 polymorphisms in these patients.
Results: Logistic regression analyses showed that the GSTM1-null allele was associated with a significantly increased risk of endometriosis and smoking with a decreased risk of endometriosis separately. There was no association between endometriosis and the GSTT1-null allele. The interaction of smoking and GST polymorphisms showed a joint effect. We found that the GSTM1-null allele was more prevalent in active smoking endometriosis patients (63.4%) than in the controls (35.0%), and the difference was statistically significant. A similar tendency was also observed in the GSTT1 allele distribution.
Conclusion: Genetic factors could modify the response to environmental pollutants in endometriosis.