Counting Crohn’s
29 June 2008
The study also identified a number of potential targets for drug development, and revealed surprising new links between Crohn’s and other common diseases, including asthma.
The first two Crohn’s susceptibility genes were discovered in 2001, followed by a third in 2006. The Wellcome Trust Case Control Consortium and parallel studies took that number above ten the following year. Now researchers have linked 32 genetic regions to susceptibility to Crohn’s.
The team of scientists and clinicians involved used DNA samples from almost 12 000 people. Many were from UK patient collections and analysed originally in the Case Control Consortium. Others came from European and North American collections.
“We now know of more than 30 genetic regions that affect susceptibility to Crohn’s disease,” says Dr Jeffrey Barrett from the Wellcome Trust Centre for Human Genetics at the University of Oxford, lead author of the study. “These explain only about a fifth of the genetic risk, which implies that there may be hundreds of genes implicated in the disease, each increasing susceptibility by a small amount.
“While this study shows the power of genome-wide association studies to reveal the genetics behind common diseases, it also highlights the complexity of diseases such as Crohn’s.”
Barrett JC et al. Genome-wide association defines more than 30 distinct susceptibility loci for Crohn’s disease. Nat Genet 2008;40(8):955–62.