Liu, X., Campbell, M. R., Pittman, G. S., Faulkner, E. C., Watson, M. A. & Bell, D. A. Expression-based discovery of variation in the human glutathione S-transferase M3 promoter and functional analysis in a glioma cell line using allele-specific chromatin immunoprecipitation. Cancer Res. 65, 99-104

Laboratory of Computational Biology and Risk Analysis, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA.
Cancer Research (Impact Factor: 9.33). 02/2005; 65(1):99-104.
Source: PubMed


Discovery and functional evaluation of biologically significant regulatory single nucleotide polymorphisms (SNP) in carcinogen metabolism genes is a difficult challenge because the phenotypic consequences may be both transient and subtle. We have used a gene expression screening approach to identify a functional regulatory SNP in glutathione S-transferase M3 (GSTM3). Anttila et al. proposed that variation in GSTM3 expression was affected by exposure to cigarette smoke and inheritance of the GSTM1-null genotype. To investigate the mechanism of GSTM3 expression was affected by exposure to cigarette smoke and inheritance of the GSTM1-null genotype. To investigate the mechanism of GSTM3 expression variation, we measured GSTM3 expression in lymphoblast cells from a human Centre d'Etude du Polymorphisme Humain family and observed a low expression phenotype. Promoter sequencing revealed two novel GSTM3 promoter SNPs: A/C and A/G SNPs, 63 and 783 bp upstream of the codon 1 start site, respectively. In this pedigree, the two children homozygous for the -63C/C genotype had 8-fold lower GSTM3 expression relative to the two children with the -63A/A genotype, with no association between A-783G SNP and GSTM3 expression. Further evaluation using genotyped glioma cell lines and with luciferase reporter constructs showed that the -63C allele was associated with lower GSTM3 expression (P < 0.0001 and P < 0.003). RNA pol II chromatin immunoprecipitation was combined with quantitative probed-based allelic discrimination genotyping to provide direct evidence of a 9-fold reduced RNA pol II binding capacity for the -63C allele. These results show that the GSTM3 -63C allele strongly affects gene expression in human cell lines and suggests that individuals who carry the low expression allele may be deficient in glutathione transferase catalyzed biological functions.

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Available from: Gary Pittman, Apr 18, 2014
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    • "These are the rare Gln 174 Trp (G 174 W), the more common Val 224 Ile (V 224 I) substitutions, and the transversion of A with C at -63 position in promoter region of GSTM3 (-62A>C) (Liu et al., 2005; McIlwain et al., 2006). The variant 174Trp allele, as well as the wild-type 224Val allele, were reported to exhibit decreased catalytic activity, whereas the variant -63C allele was associated with increased expression of the gene (Liu et al., 2005; McIlwain et al., 2006). "

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    • "The same effect was demonstrated independently by in vitro transcription (N'Diaye, Pastinen, Paterson, Larivière, Labuda, Hudson, and Sinnett, unpublished data) of cloned constructs of the 2-kb BTN3A2 haplotypes from the present study. Similarly, in GSTM3, the functional analysis of its rs1332018G4T polymorphism (originally À63 A/C in Liu et al. [2005]) has shown eight-fold lower transcription activity of the G allele related to its nine-fold reduced RNA Pol II binding capacity [Liu et al., 2005]. "
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