ABCB1 polymorphism and susceptibility to acute lymphoblastic leukemia: a meta analysis

Background: A large body of studies has investigated the potential role of ABCB1 polymorphism in ALL susceptibility. However, the results are conflicting. The aim of the present meta-analysis was to define the effect of ABCB1 polymorphism on ALL risk. Methods: We identified 8 eligible studies involving 1,308 cases and 1,427 controls through searching PubMed and Enbase databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to access the strength of the association with both fixed effects and random effect models. Results: We found ABCB1 polymorphism was associated with an increased risk of ALL under the homozygote genotypes (TT vs. CC: OR, 1.29, 95% CI, 1.08-1.54), the recessive model (TT vs. CT + CC: OR, 1.47, 95% CI, 1.02-2.13) and the allele model (T vs. C: OR, 1.14, 95% CI, 1.04-1.25). Similar results were indicated in Asian populations (TT vs. CC: OR, 1.79, 95% CI, 1.32-2.43; TT vs. CT + CC: OR, 2.55, 95% CI, 1.47-4.43; T vs. C: OR, 1.38, 95% CI, 1.18-1.62), but not in Caucasian populations. Conclusions: These findings indicate that ABCB1 polymorphism may play a critical role in the development of ALL in Asians.