OBJECTIVETo study the relationship between occupational hazard susceptibility of formaldehyde and genetic polymorphisms of ALDH2 and CYP2E1.

METHODSGenotypes of ALDH2 and CYP2E1 (Rsa I/Pst I site) of 107 subjects exposed to formaldehyde were determined with PCR-RFLP through testing peripheral blood lymphocytes, and the concentration of air formaldehyde in workplace and urine formic acid of the subjects were measured with HPLC. The relationship between genotypes and the urine formic acid increment was analyzed with nonparametric rank sum testing.

RESULTSThe concentration of urine formic acid increment was related with ALDH2 genotypes (chi2 = 9.241, P < 0.05), and the means of urinary formic acid of subjects with GG, GA, AA genotype were (15.84 +/- 6.86), (12.06 +/- 7.94) and (7.31 +/- 5.37) mg/g creatinine, respectively. Mann-Whitney U test showed the formic acid increment between allele G homozygotes and allele A homozygotes was significantly different (U=26, P= 0.033). Our data indicated that the formaldehyde metabolism of ALDH2 GG homozygotic genotype was more active than ALDH2 AA homozygotic genotype(the difference of the two mean rank was 13.30). But the polymorphism of Rsa I / Pst I site of CYP2E1 5'-franking region was not correlated with the concentration of urine formic acid (chi2 = 4.285, P=0.117), and the urinary formic acid means of subjects with C1/C1, C1/C2, C2/C2 genotype were (11.14 +/- 7.91), (12.13 +/- 8.16) and (16.51 -/+ 3.78) mg/g creatinine, respectively. By Stepwise Multiple Regression Analysis, it showed that the urinary formic acid increment might be influenced by FA exposure concentration and ALDH2 genotype, and the model's R2 was 0.196.

CONCLUSIONThe metabolism of formaldehyde in human body was related with the genotypes of ALDH2, but not with the CYP2E1 (Rsa I/Pst I) polymorphisms.