Abstract
Background: Chronic Arsenic exposure causes skin manifestations and even cancer. However, the response varies widely among persons despite receiving similar cumulative exposure through their food or drinking water or both. These differentiations in manifestations may be due to polymorphic distribution of arsenic metabolizing genes among exposed people. Method: Polymorphism of GSTO1, GSTO2 and their frequency distribution may modify skin manifestations and development of arsenic induced cancer in exposed persons through food chain. Polymorphic variations of GSTO1 and GSTO2 have been studied on 112 subject including control. They were recruited from one of major arsenic affected district, Nadia of West Bengal, India, having high arsenic content in their food. Exposed subjects were categorized into three groups, i.e, with arsenical skin lesions and with out arsenical skin lesions and arsenic induced cancer. Control subjects were 33 in number. Concentration of arsenic in their urine, hair, drinking water, food, extent of clinical manifestations, GST O1and O2status was determined. DNMT1, 3A, and 3B were studied for their expression profile and analyzed with GSTO1 and O2 polymorphisms. Result: Genetic polymorphism of GSTO1 gene polymorphism is significantly associated with arsenic induced skin scores in skin lesion positive cases and arsenic induced cancer cases and also significant increase is seen in DNMT expression and MDA level in exposed cases with homozygous wild type variants. Total urinary arsenic decreases significantly in wild type GSTO1 genotype, although, GSTO2 polymorphism showed no statistically significant differences in skin manifestations, and DNMTs expression. Frequency of GSTO1 and O2 polymorphic variety showed prevalence of wild type homozygous in arsenic induced cancer cases.Conclusion: GSTO1 polymorphism shows significant association with DNMT expression profile in arsenic exposed people.
Arsenic levels in drinking water and the prevalence of skin lesions in West Bengal, India
