Glutathione S-transferase polymorphisms and their role in recurrent pregnancy loss: A genetic risk assessment

Objective: The frequency of recurrent pregnancy loss in society is 3-5%. Experts suggest that genetics account for over 80% of unexplained recurrent pregnancy loss. Glutathione S-transferase (GST) enzymes, regulated by GST genes, facilitate the detoxification of a variety of naturally occurring metabolites as well as environmentally derived chemicals. This research aimed to investigate GST gene polymorphisms as a potential risk factor in recurrent pregnancy loss etiology in the Turkish population. Materials and Methods: This study involved 107 recurrent pregnancy loss patients who sought treatment at the Sivas Cumhuriyet University Faculty of Medicine, Department of Medical Genetics, along with a control group of 107 individuals who had a successful birth and no previous history of miscarriage. The multiplex polymerase chain reaction and restriction fragment length polymorphism techniques were employed to analyze GSTM1, GSTT1 and GSTP1 gene polymorphisms in these cases. Results: GSTT1 null genotype (X2=4.74; p=0.029) and GSTT1/GSM1 null genotype (X2=3.333; p=0.047) were associated with statistically significant differences between the study groups. No statistical significance was detected when considering the GSTM1 null genotype (X2=3.326; p=0.068) or the GSTM1/GSTP1 and GSTT1/GSTP1 gene polymorphisms. Conclusion: A statistically significant association was observed between the GSTT1 null genotype and the diseased group. Our research demonstrated a substantial increase in the risk of recurrent pregnancy loss in the Turkish population, specifically among individuals with the GSTM1-null genotype. No statistical correlation was found between the GSTM1 and GSTP1 gene polymorphisms and recurrent pregnancy loss. Furthermore, no statistical significance was observed when they were assessed together.