Lack of Association Between GSTM1 and GSTT1 Polymorphisms and Brain Tumour Risk

Objective: Glutathione S-transferases (GSTs) are important enzymes that are involved in detoxification of environmental carcinogens. Molecular epidemiological studies have been conducted to investigate the association between GSTM1 and GSTT1 homozygous deletion polymorphisms and brain tumours but results have been conflicting. The aim of this study was to clarify this problem using a meta-analysis. Methods: A total of 9 records were identified by searching the PubMed and Embase databases. Fixed- and random-effects models were performed to estimate the pooled odds ratios. Results: No significant association was found between the GSTM1 and GSTT1 homozygous deletion polymorphisms and risk of brain tumours, including glioma and meningioma. Similar negative results were also observed in both population-based and hospital-based studies. Conclusion: These findings indicate that the GSTM1 and GSTT1 polymorphisms may not be related to the development of brain tumours.