Genetic Polymorphisms of GSTM1 and GPX1 Genes and Smoking Susceptibility in the Saudi Population

Abstract

Background/Objective/Methods: Glutathione-S-transferase Mu1 (GSTM1) and glutathione peroxidase 1 (GPX1) are known antioxidant enzymes that help protect cells from the oxidative damage that occurs from smoking. This study explored the correlation between GSTM1 and GPX1 levels between a group of smokers with the GSTM1 and GPX1 genes in the Saudi population and a control group and investigated the genetic risk factors in the group of smokers. Results: The control and smokers’ group (n = 50; aged 22.3 ± 3.1 years; BMI 24.6 ± 5.9 kg/m 2 ) were genotyped using quantitative polymerase chain reaction (qPCR). In comparison with the control group, the smokers’ group displayed a different genotype disruption of GSTM1 and GPX1. Carriers of the homozygous (TT) genotype of GSTM1 had more than a twofold (OR = 2.71, 95% CI = 0.10–70.79, P = 1.000) smoking risk than the carriers of the heterozygous (CT) genotype. Those with the GPX1 gene showed no risk in the control and smokers’ groups. Smokers with the TT/GG combination (homozygous for GPX1 and normal for GPX1) were identified as high risk (OR = 2.58, 95% CI = 0.096–69.341). Conclusion: The main outcomes showed no significant association between genetic polymorphism of the GSTM1 and GPX1 genes and cigarette smoking in the Saudi Arabian population. However, the results showed a slight decrease in the number of GSTM1 and GPX1 gene modifications among smokers.