The most consistently described associations in ulcerative colitis have been with human leukocyte antigen class II alleles.
Dr Laura Fernández looked for associations among distinct genetic polymorphisms in the major histocompatibility complex.
that might play a role in determining the susceptibility to ulcerative colitis and especially to the extensive form of the disease.
The researchers performed a case-control study with a total of 253 patients with ulcerative colitis and 315 healthy controls recruited from a single Spanish center.
|Alleles DRB1*0103, IKBL+738(C) and BAT_2-8 were increased in patients with ulcerative colitis|
|Inflammatory Bowel Diseases|
All the samples and 4 cell lines carrying DRB1*0103 or DRB1*1501 alleles were typed for the human leukocyte antigen class II and class III gene markers.
The research team found that the frequency of the alleles DRB1*0103, IKBL+738(C) and BAT_2-8 was increased in patients compared with controls.
The team noted that the associations were greatest in patients with extensive disease compared with patients with distal disease.
The team assessed the allelic combination DRB1*0103/D6S273-5/BAT_2-8/TNFa11b4c1d3e3/IKBL+738(C)/MICA51 including telomeric class III markers of the 7.1 ancestral haplotype.
The researchers found that this combination is highly increased in patients with ulcerative colitis, especially in those with the extensive form of the disease.
Dr Fernández's concluded, “The above-mentioned pattern, most likely formed by recombination of the telomeric fragment of the major histocompatibility complex ancestral 7.1 haplotype, seems to be the most important genetic determinant of susceptibility to the extensive form of ulcerative colitis in our population.”