Glutathione s-transferase m1 and t1 polymorphisms and susceptibility to oxidative damage in healthy korean smokers

Abstract

Aims: The relationship between glutathione S-transferase (GST) polymorphisms and susceptibility to smoking-induced oxidative damage was investigated in healthy Korean smokers.

Methods: Forty-nine healthy male smokers (20-59 years) participated in the study. GSTT1 and GSTM1 genotypes were determined, and lymphocyte DNA damage was assessed by the Comet assay.

Results: Out of the 49 smokers, 20 individuals were GSTT1 positive and 29 were GSTT1 null. For GSTM1, 45 smokers were GSTM1 positive and 4 were GSTM1 null. HDL cholesterol levels (p = 0.011) and the atherogenic index of plasma (p = 0.01) were significantly reduced, and concentrations of conjugated dienes were increased (p = 0.01) in the GSTT1-null individuals but not in the GSTT1-positive individuals. The GSTT1-null individuals were more susceptible to DNA damage than the GSTT1-positive individuals. For all parameters, the GSTM1 genotypes were excluded from statistical analyses due to the small number of subjects with the GSTM1-null type.

Conclusions: Our findings suggest that subjects with the GSTT1-null genotype were more susceptible to oxidative damage than the GSTT1-positive subjects. Therefore, the GSTT1-null genotype may confer an increased risk of smoking-related cardiovascular disease.