Current advances of genetics in Inflammatory Bowel Disease

Abstract

Genetic factors play an important role in the pathogenesis
of inflammatory bowel diseases (IBD), including both ulcerative
colitis (UC) and Crohns disease (CD). The research
on genetic susceptibility of IBD has been tremendous
and over 10 chromosomal regions have been identified
by genome-wide scanning. The certain replicated linkage
region in different studies, IBD1 (16q12), contains the
CD susceptibility gene, NOD2/CARD15. Further fine mapping
as well as candidate gene studies have already led to
the identification of a number of other susceptibility genes
including DLG5, OCT1 and 2, NOD1, HLA, and TLR4.
Recent studies, particularly in CD, have highlighted a
number of associations between genotype and phenotype.
These, suggest that genetics also may influence the clinical
manifestations of IBD including disease location, behavior,
natural history and side effects of drug therapy. Genetic
research in IBD has helped our understanding of the clinical
heterogeneity of the disease and has started to explore
the complex interactions between genetic risk factors and
environmental risk factors in IBD. Although rapid advances
in genomic medicine are yet to impact on routine clinical
practice, it is anticipated that genetic markers in the
future will be implemented in an integrated molecular diagnostic,
therapeutic and prognostic approach of IBD patients.