Individual effects of GSTM1 and GSTT1 polymorphisms on the risk of polycystic ovarian syndrome: a systematic review and meta-analysis

Objective: Polycystic ovarian syndrome (PCOS) is one of the most common endocrinologic disorders in women. It is widely believed that oxidative stress plays a significant role in the pathophysiology of PCOS. The glutathione S-transferases (GST) are a class of enzymes that safeguard cells against oxidative stress. However, published research on the correlation between the GSTT1 and GSTM1 polymorphisms and the risk of PCOS has yielded conflicting results. That’s why a meta-analysis was carried out to evaluate the effects of GSTT1 and GSTM1 polymorphisms on PCOS.
Materials and Methods: The databases of Embase, PubMed, Scopus, Web of Science and google scholar were thoroughly scrutinized to identify studies that met the eligibility criteria. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the GSTT1 and GSTM1 polymorphisms in relation to PCOS were derived using fixed-effects or random effects models. The subgroup analyses were performed based on ethnicity, mean age of participants and the PCOS diagnostic protocols.
Results: Screening determined that five studies involving a total of 1607 participants (872 in the PCOS group and 735 in the control group) were deemed viable for inclusion in the meta-analysis. Overall analysis showed that GSTM1 null and GSTT1 null were not associated with an increased risk of PCOS (OR: 0.925, 95% CI: 0.755-1.134; OR: 1.175, 95% CI: 0.614-2.247 respectively). Egger’s and Begg’s tests indicated no publishing bias.
Conclusion: This meta-analysis confirmed that GSTM1 and GSTT1 polymorphisms were not associated with an increased risk of PCOS. However, more studies are needed to prove this claim.