Abstract:
Acute lymphoblastic leukemia is the most common cancer in childhood. Many factors including xenobiotic-metabolizing enzymes genetic polymorphisms (e.g., cytochrome P-450 (CYP), glutathione-S-transferase (GST), or NAD(P)H: quinone oxidoreductase (NQO1), and the environment factors (e.g., pesticides, herbicides, or insecticides) are associated with increased risk of childhood ALL. In this study, we determined the relationship between the polymorphisms in genes encoding -metabolizing enzymes GSTM1, GSTT1, CYP1A1 and NQO1, and pesticides exposure and the risk for ALL in 139 children with ALL and 139 age-sex-matched children. We found that combination of GSTM1 null and CYP1A1*2A were both found to be significantly associated with increased risk of ALL (OR=2.48, 95% CI 1.24-4.97), but not GSTT1, CYP1A1*2B or NQO1, history of pesticides exposure was also significantly associated with increased risk of ALL (OR=2.29, 95% CI 1.54-3.47). These results suggest that the combined effect of polymorphisms in GSTM1 and CYP1A1*2A gene and pesticides exposure factor might contribute to increased risk of ALL in Thai children.