Are polymorphisms in metabolism protective or a risk for reduced white blood cell counts in a Chinese population with low occupational benzene exposures?

Int J Occup Environ Health. 2015 Jul-Sep;21(3):232-40. doi: 10.1179/2049396714Y.0000000091. Epub 2015 Jul 16.

Abstract

Background: Genetic variations in metabolic enzyme genes may enhance hematotoxicity in benzene-exposed populations.

Objective: To investigate the association between polymorphisms of metabolism genes and white blood cells (WBCs).

Methods: Three hundred and eighty-five benzene-exposed workers and 220 unexposed indoor workers were recruited in China. We explored the relationship between metabolic enzymes polymorphisms [glutathione S-transferase T1/M1 (GSTT1/M1) null, glutathione S-transferase P1 (GSTP1)rs1695, Cytochrome P450 2E1 (CYP2E1) rs3813867, rs2031920, rs6413432, microsomal epoxide hydrolase (mEH) rs1051740, rs2234922] by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis and WBC.

Results: The exposed group had lower WBC counts (P<0·001) than the unexposed group. Increased susceptibility to hematotoxicity, as evidenced by lower WBC counts, was found in workers with null-GSTT1 (P = 0·045), null-GSTM1 (P = 0·030), rs2031920 (P = 0·020), and rs3813867 (P = 0·014) genotypes. White blood cell counts were also lower in workers with null-GSTT1 and null-GSTM after adjusting for age, gender, smoking, and alcohol consumption.

Conclusion: Null-GSTT1 and null-GSTM1 genotypes and Cytochrome P4502E1 (CYP2E1: rs2031920, rs3813867) may support the hematotoxicity of benzene-exposed workers in China, and we can make use of it to select susceptible population.

Keywords: Benzene,; CYP2E1,; GSTs,; Genetic polymorphism,; White blood cell,; mEH.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Air Pollutants, Occupational* / adverse effects
  • Air Pollutants, Occupational* / analysis
  • Asian People / genetics
  • Benzene* / adverse effects
  • Benzene* / analysis
  • Cytochrome P-450 CYP2E1 / genetics
  • Epoxide Hydrolases / genetics
  • Female
  • Genetic Predisposition to Disease*
  • Glutathione S-Transferase pi / genetics
  • Glutathione Transferase / genetics
  • Humans
  • Leukocyte Count*
  • Male
  • Middle Aged
  • Occupational Exposure* / adverse effects
  • Occupational Exposure* / analysis
  • Polymerase Chain Reaction
  • Polymorphism, Genetic
  • Polymorphism, Restriction Fragment Length
  • Risk
  • Young Adult

Substances

  • Air Pollutants, Occupational
  • Cytochrome P-450 CYP2E1
  • glutathione S-transferase T1
  • GSTP1 protein, human
  • Glutathione S-Transferase pi
  • Glutathione Transferase
  • glutathione S-transferase M1
  • Epoxide Hydrolases
  • Benzene