title: Single nucleotide polymorphisms in the XPG gene: determination of role in DNA repair and breast cancer risk.
abstract: In this study we determined the effect of single nucleotide polymorphisms in the XPG gene on DNA repair and breast cancer susceptibility. Ninety individuals, with previously studied DNA repair rate at 24 hr of 2 types of UV-specific cyclobutane pyrimidines dimers (CPDs) in skin were genotyped for XPG polymorphism at codon 1104 (exon 15 G>C; Asp > His). The repair rate of TT=C dimer was similar in both wild-type GG homozygotes and GC heterozygotes, whereas, for TT=T, dimer repair was non-significantly (Student's t-test, p = 0.34) lower in GC heterozygotes than wild-type GG homozygotes. Genotyping of 220 breast cancer cases and 308 controls for the same single nucleotide polymorphism in exon 15 of the XPG gene exhibited marginally significant increased frequency of the variant allele (chi(2) 3.84, p = 0.05; OR 1.33, 95% CI 1.0-1.8) in cases (C-allele 0.29) compared to controls (C-allele 0.24). Combined heterozygote and variant homozygote genotype frequency was also higher in cases than controls (chi(2) 4.79, p = 0.03; OR 1.50, 95%CI 1.04-2.16).
authors.affiliation: Department of Biosciences, Center for Nutrition and Toxicology, Karolinska Institute, Novum, Huddinge, Sweden. rajiv.kumar@cnt.ki.se
authors.forename: Rajiv
authors.initials: R
authors.lastname: Kumar
authors.forename: Lotta
authors.initials: L
authors.lastname: Höglund
authors.forename: Chunyan
authors.initials: C
authors.lastname: Zhao
authors.forename: Asta
authors.initials: A
authors.lastname: Försti
authors.forename: Erna
authors.initials: E
authors.lastname: Snellman
authors.forename: Kari
authors.initials: K
authors.lastname: Hemminki
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D001943:Breast Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016022:Case-Control Studies; D004260:DNA Repair / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D004720:Endonucleases / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors; D014157:Transcription Factors; D000099250:DNA Excision Repair Protein ERCC-5
chemical_list: D004268:DNA-Binding Proteins; D004720:Endonucleases; D009687:Nuclear Proteins; D014157:Transcription Factors; D000099250:DNA Excision Repair Protein ERCC-5