Tamer et al. [58] analyzed glutathione S-transferases (GSTs) genotypes in association with smoking and revealed that the GSTM1 null genotype was associated with an increased gastric cancer risk for smokers (odds ratio (OR) = 2.15; 95% CI, 1.02–4.52), whereas no significant differences in the distributions of any of the other GST genes, GSTT1 and GSTP1, existed in the Turkish population. This evidence concerns the gene HPGDS and gastric cancer.