GSTM1 and precursor B-cell acute lymphoblastic leukemia: The present study successfully genotyped 150 B-ALL patients comprising 92 (61%) males and 58 (39%) females with 126 (84%) cases from the rural and 24 (16%) from the urban dwelling having a median age of 16 years (range 2–58 years) along with 150 age [median 17 years (range 5–62 years)] and gender matched, leukemia free, healthy control subjects for GSTT1, GSTM1, GSTP1, GSTO1, and GSTO2 SNPs.