Genetics of inflammatory bowel disease: where are we?

Abstract

Recent advances in recombinant DNA technology have rendered feasible the application of a positional cloning strategy to the identification of inflammatory bowel disease (IBD) susceptibility genes. In this context many groups have now performed genome-wide scans on multi-case IBD families so as to identify chromosomal loci showing linkage with IBD. The results of such studies have revealed a number of suggestive susceptibility loci, some of which have been independently replicated, but none of which has been found uniformly in all studies. At present the reasons for such disparities remain unclear, but the available linkage data suggest that IBD gene discovery can be achieved by positional cloning. It seems likely, however, that this work will be greatly expedited through the use of several technologies which complement the positional cloning approach, including, for example, expression array and candidate gene analysis. Availability of these strategies together with the progress already made in relation to the genetics of IBD should render feasible relatively rapid isolation of IBD susceptibility genes and the translation of such information to clinical benefit.