We found that patients with variant genotype (A/G) of GSTP1 had higher risk of grade 2 anemia than wild type (A/A) which presented in 81.82% compared with 46.34% (OR=5.2; 95%CI: 1.000-27.146; =0.036), as presented in Table 5. Here, GSTP1 is linked to anemia (phenotype).