Analysis of Single Nucleotide Polymorphisms in CD14 and Tumor Necrosis Factor α Gene Promoters in Inflammatory Bowel Disease

摘要

To clarify the genetic predisposition to two inflammatory bowel diseases, ulcerative colitis (UC) and Crohn's disease (CD), we analyzed the allele and genotype frequencies of the single nucleotide polymorphisms (SNPs) at -159 (T/C) of CD14 gene and at -1031 (C/T), -863 (C/A) and -857 (C/T) of the tumor necrosis factor α (TNF-α) gene in 98 patients with UC and 79 patients with CD. The frequency of homozygous genotype -159 (C/C) of CD14 gene was decreased in both UC and CD. The T allele frequency at position -857 of TNF-α gene was higher in UC and lower in CD than in control subjects. The frequencies of genotypes -1031 (T/T) and -863 (C/C) of the TNF-α gene were higher in patients with UC with proctitis, and the frequency of the C allele at position -863 of the TNF-α gene was decreased in patients with UC involving the colon. The allele and genotype distributions at position -159 of CD14 gene were similar among the subgroups of patients with UC and CD. The SNP at position -159 of the CD14 gene promoter may indicate a genetic predisposition factor for inflammatory bowel disease, where as the SNP at position -857 of the TNF-α gene promoter may represent the linkage disequilibrium with HLA-DR.