Glycine N-methyltransferase affects urinary 1-hydroxypyrene and 8-hydroxy-2'-deoxyguanosine levels after PAH exposure

Objectives: The object of this study was to assess the modulating effects of genetic polymorphisms of glycine N-methyltransferase (GNMT) genotypes on 1-hydroxypyrene (1-OHP) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in urine from coke-oven workers, consistently exposed to polycyclic aromatic hydrocarbons (PAHs). Methods: The study participants included 289 coke-oven workers from a steel company in Taiwan. Personal air samples, spot urine samples, peripheral blood samples, and questionnaires were used to quantify PAH exposure, oxidative DNA damage, GNMT gene polymorphisms, demographic data, and environmental pollutants. Results: Urinary 1-OHP level, GNMT STRP1 genotype, and worksite were significant predictors of urinary 8-OHdG levels after adjustments were made for covariates. Conclusions: This study suggests that GNMT STRP1 could modulate urinary 1-OHP and 8-OHdG levels in coke-oven workers exposed to PAHs.