Genetics and IBD

I found the genetic aspect of CD (Crohn’s Disease) and UC (ulcerative colitis) that was explored in the articles entitled Inflammatory Bowel Disease: Cause and Immunology, Inflammatory Bowel Disease: Past, Present, and Future, as well as Translational Research in Inflammatory Bowel Disease to be interesting. Each of these three articles explored the genetics behind the susceptibility to IBD. Some genetic facts that were listed include: “Approximately 10-15% of IBD cases are familial, with familial clustering of CD and UC families occurring such that 75% of families are concordant for disease type, and 25% have both CD and UC within the same family” (Translational Research in Inflammatory Bowel Disease, Abreu, M., Sparrow, M.). Also, The research conducted with monozygotic twins revealed that there is a “pooled concordance in monozygotic twins of 37.3% for CD and 10% for UC” (Inflammatory Bowel Disease: Cause and Immunology, Baumgart, D., Carding, S.). It was also interesting to see that there was a less significant link between dizygotic twins (7% for CD and 3% for UC, according the same article). Furthermore, the linkage of genetic predisposition to CD was found to be stronger than that of UC. It was found that UC and CD have susceptibility regions on 12 chromosomes labeled as IBD1-9 and CARD15 (NOD2). Genetics appears to play a large role in susceptibility to IBD, however there are also links to environmental factors. The article Inflammatory Bowel Disease: Cause and Immunology mentions many environmental factors that have been shown to contribute to IBD, however it would be interesting to further understand why these factors increase risk. Also, for further research, I found an article entitled “Clinical Aspects and Pathophysiology of Inflammatory Bowel Disease” by Hendrickson, B., Gokhale, R., and Cho, J. from the Clinical Microbial Reviews. http://cmr.asm.org/cgi/content/full/15/1/79