In contrast, a significant association was observed between the NAT2 rs1799931G>A polymorphism and decreased cancer susceptibility in overall meta-analysis (AA vs. GG: OR=0.55, 95% CI=0.33-0.93; GA vs. GG: OR=1.00, 95% CI=0.88-1.14; dominant model: OR=0.97, 95% CI=0.86-1.10; recessive model: OR=0.56, 95% CI=0.34-0.94) and the Asian group (AA vs. GG: OR=0.50, 95% CI=0.26-0.94; recessive model, OR=0.50, 95% CI=0.27-0.94).
The extraction method was combined with newly designed PCR-based assays for cancer susceptibility marker genes such as CYP1A1 (exon 7), CYP2E1 (Dra1, Rsa1), GSTM1 and NAT2 [NAT2*5A (C481T), NAT2*6A (G590A), NAT2*7A (G857A)].