Association Of Genetic Polymorphisms Of The DNA Repair Gene XPD With The Risk Of Arsenism

Objective: Chronic exposure to inorganic arsenic is know to cause arsenism and internal cancers in humans. This study was undertook to examine whether genetic susceptibility, as determined by the codon 751 SNP and codon 312 SNP of the DNA repair gene XPD, influences the risk of arsenism and cytokine levels and anti-lipid peroxidation ability, in a case-control study. Methods: Genetypes were determined by PCR-restri-ction fragment length polymorphism approaches in 88 health controls and 81 patients with arsenism. Interleukin-2 (IL-2), Interleukin-8 (IL-8), tumornecrosis factor-α (TNF-α), superoxide dismutase(SOD), glutathione peroxidase(GSH-Px) and malondialdehyde(MDA) in the serum were measured and analyzed. Results: 1)Compared with those of the control, the IL-2, IL-8, TNF-a, MDA levels were higher, while the SOD, GSH-Px contents were lower in the patients. 2) The frequency of XPD 312 Asp/Asp was significantly lower in patients than that of the controls. Individuals carrying at least one 312 Asn variant allele were at an increase risk for arsenism as compared with those with the 312 Asp/Asp genetype. The OR was 2.07. The frequency of XPD751Lys/Lys was significantly lower in patients than that of the controls. Individuals carrying at least one 751 Gln variant allele were at an increase risk for arsenism as compared with those with the 751 Lys/Lys genetype. The OR was 2.39. However, the linka disequilibrium of these 2 loci were not found.