Tumor Necrosis Factor Alpha Extended Haplotypes and Risk of Gastric Carcinoma

摘要: The tumor necrosis factor α ( TNF A)-308*A allele has been found to confer an increased risk of gastric carcinoma. Inconsistency in estimates across populations lead us hypothesize about the presence alternative causal locus same chromosomal region. A suitable approach is determine haplotypic structure order clarify whether association between *A and carcinoma etiologic or secondary linkage disequilibrium. Firstly, we assessed TNFA -308G>A polymorphism a population from Northern Portugal (508 patients, 713 controls); secondly, genotyped five microsatellite loci (TNFa, b, c, d, e) flanking A-308G>A establish associated with this single-nucleotide cases (122 patients) controls (169 individuals). We significant (odds ratio, 1.7; 95% confidence interval, 1.3-2.2) confirming previous results our population. Regarding allele–associated haplotypes, most relevant difference was for H1A haplotype present 33.1% 12.5% controls. also observed haplotypes that were only differentiation test showed control groups significantly different structure. This suggests dependent on disequilibrium as yet unidentified locus. (Cancer Epidemiol Biomarkers Prev 2008;17(9):2416–20)