[Influence of MDR1 gene C3435T on peripheral white blood cell counts in workers exposed to benzene].

Objective: To explore the effects of MDR1 C3435T on the peripheral white blood cell counts in workers exposed to benzene.

Methods: One hundred and twenty-one benzene-exposed workers and 110 healthy controls without benzene exposure were enrolled in this study. White blood cell counts influenced by the polymorphism of MDR1 gene were analyzed.

Results: The frequency of MDR1 3435 C/C, C/T, T/T in healthy controls was 37.27%, 46.36%, 16.37%, respectively, and it was 38.84%, 41.33%, 19.83% in the benzene-exposed workers, respectively. The frequency of the MDR1 gene was also not significantly different between benzene exposed workers and controls. Subjects exposed to benzene with MDR1 3435 mutation genotype (T/T) had the significantly lower WBC [(5.46 ± 1.51) × 10(9)/L] than those carrying wild type (C/C) and heterozygous (C/T), whose WBC were (6.08 ± 1.28) × 10(9)/L (P = 0.044).

Conclusion: P-glycoprotein encoded by MDR1 gene may be implicated into the hematotoxicity of benzene. Subjects carrying MDR1 3435 T/T genotype may have a higher risk of benzene poisoning.