This article reviews current knowledge of the role of HLA complex genes …

• Abstract
• Introduction
• Classical HLA class II genes
• HLA Class II associations with Crohn's disease
• HLA Class II associations with ulcerative colitis
• HLA Class II associations with the extra-intestinal manifestations
• Observations on HLA Class II associations with IBD
• Other genes in the HLA complex
• Does HLA determination have a role in clinical practice?
• References
• Figure

Figure 1 Crohn's disease map of chromosome 6p and the HLA region. The IBD susceptibility locus IBD3 is here defi ned by a 34cM chromosomal bin (6.2), which reached genome wide signifi cance for IBD in the genome scan meta-analysis of van Heel et al[10]. The IBD3 region encompasses the ~ 4MB HLA region shown in detail on the right of the fi gure. White, grey, striped and black boxes show expressed genes, gene candidates, non-coding genes and pseudogenes, respectively. Genes with polymorphisms ssociate with IBD are shown in red. Modifi ed with permission from Shiina et al[61].