Background/aims: Although primary sclerosing cholangitis is believed to be an autoimmune disorder, no tissue-specific auto-antibodies have yet been identified, and the strongest support for an autoimmune aetiology comes from HLA-association studies. Three different HLA haplotypes are associated with susceptibility to the disease and one with protection from it. These HLA haplotypes, however, do not account for all of the disease risk and genes outside the HLA region may also have a role in disease pathogenesis. The aim of this study was to investigate, for the first time, polymorphic genes/sites within the interleukin-1 and interleukin-10 genes in a large well-characterised group of patients.
Methods: Ninety-six patients and 96 control subjects were studied. A single base-exchange polymorphism at position +3953 in the first exon of the IL-1B gene, a penta-allelic repeat sequence in the IL-1 receptor antagonist gene (IL-1RN) and three single base-exchange polymorphisms at positions -592, -819 and -1082 in the IL-10 gene promoter were determined by standard PCR-based techniques.
Results: Overall, there was no significant difference in the distribution of any of the IL-1B, IL-1RN or IL-10 alleles or genes sequences comparing patients and controls. In addition, there was no difference when the patients were stratified for the presence and absence of the HLA DRB1*0301 (DR3) allele or concurrent inflammatory bowel disease.
Conclusion: Neither the IL-1B +3953, IL-1RN microsatellites polymorphisms on chromosome 2q13 nor the IL-10 -592, -819, -1082 promoter gene polymorphisms on chromosome 1q31-32 are associated with susceptibility or resistance to primary sclerosing cholangitis.