Genome-wide scans have implicated several susceptibility loci, but linkage of 19p13 (IBD6) to Crohn's disease (CD) has not been fully replicated.
Here, researchers from England report a replication study of IBD6 in a Caucasian population.
The team included 284 affected sibling pairs from 234 families.
|Limited disease extent was associated with homozygosity of the G241 allele.|
|Inflammatory Bowel Diseases|
They examined 2 candidate genes (DDXL and ICAM-1) within the IBD6 locus.
The team performed a case control study with a total of 228 CD and 243 ulcerative colitis (UC) patients and 407 healthy controls.
There was no association to either UC or CD was found in 3 novel intronic single nucleotide polymorphisms (SNPs) in DDXL.
However, for ICAM-1, a significant association was found between K469 homozygosity and CD overall, as well as between E469 and fistulating disease.
In the UC group, the researchers found that limited disease extent was associated with homozygosity of the G241 allele.
Dr Jin Hong Low and colleagues concluded, "These data support linkage for CD at 19p13 and suggest that the amino acid polymorphisms in ICAM-1 may be associated with IBD".