title: Human GMDS gene fragment hypermethylation in chronic high level of arsenic exposure with and without arsenic induced cancer.
abstract: Arsenic, though a poor mutagen, is an accepted environmental carcinogen. Perturbation of DNA methylation pattern leading to aberrant gene expression has been hypothesized as the mechanism for arsenic induced carcinogenesis. We had earlier demonstrated the hypermethylation of promoter region of p53 and p16 genes in persons exposed to different doses of arsenic. Till now no genomic hot spot has been identified which is frequently hypermethylated or hypomethylated in persons chronically exposed to environmental arsenic. In the present work, we have identified one hypermethylated sequence by methyl-sensitive arbitrarily primed polymerase chain reaction in the peripheral blood leukocyte DNA of chronically arsenic exposed persons with and without arsenic induced skin cancer. The sequence is from GMDS gene responsible for fucose metabolism. Southern hybridization of the sequence to the amplification products of methyl sensitive restriction enzyme digested genome of persons exposed to different doses of arsenic indicated that methylation increased in a dose dependent manner.
authors.affiliation: Department of Biophysics, Molecular biology & Genetics, University of Calcutta, Kolkata, West Bengal 700092 India ; Department of Physiology, Presidency University, Kolkata, West Bengal 700073 India.
authors.forename: Sarmishtha
authors.initials: S
authors.lastname: Chanda
authors.forename: Uma B
authors.initials: UB
authors.lastname: Dasgupta
authors.forename: Debendranath Guha
authors.initials: DG
authors.lastname: Mazumder
authors.forename: Jayita
authors.initials: J
authors.lastname: Saha
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Gupta
keywords: Arsenic exposure; Arsenic induced cancer; GMDS gene hypermethylation