Risk Genes of Inflammatory Bowel Disease in Asia: What Are the Most Important Pathways Affected?

Genetic factors play an important role in the pathogenesis of inflammatory bowel disease (IBD), and IBD is now recognized as a complex disease that results from interplay between genetic and environment factors. To date, over 160 IBD-susceptible loci have been identified using genome-wide association studies (GWAS). The risk genes identified in these studies are involved in various pathways in innate and adaptive immune response such as innate bacterial sensing, autophagy and interleukin-23 receptor/T-helper cell 17 pathway. It was initially believed that the genetic backgrounds of Asian IBD patients differ from that of other populations. Recent GWAS and meta-analysis found that there is pervasive sharing of risk loci between the East and West. Overlapping risk genes between populations of different ancestries indicate that pathways underlying the etiology of IBD may be common between Asia and other areas. However, the importance of individual pathways may be different in Asia from the Western countries. Identifying the most important pathways affected in Asian IBD patients may provide a better understanding of pathogenesis of IBD in Asia and improve the clinical management of the patients.