The Immunochip is a custom Illumina Infinium chip comprising 196,524 SNPs and small indels selected primarily based on GWAS analysis of 12 autoimmune and inflammatory diseases. The chip has two purposes: fine mapping of 289 established associations corresponding to 187 distinct loci, and deep replication of suggestive, but not yet proven, associations. Fine-mapping regions were defined as 0.2cM centered on GWAS hit SNPs, and all SNPs and short indels in these regions from the 1000 Genomes Project low coverage pilot CEU samples, as well as variants discovered in resequencing experiments conducted by groups collaborating in the chip design were selected for inclusion. Replication of autoimmune and inflammatory GWAS (including Crohn's disease and ulcerative colitis) contributed the bulk of the remaining SNP lists. Approximately 25,000 SNPs were included as replication of unrelated diseases as part of the WTCCC2 project, which serve as useful null SNPs for these analyses. In total, approximately 240,000 SNPs were selected for inclusion, with an assay design success rate of ~80%. Reprinted from Jostins et al. (2012), with permission from Springer Nature (see <a href="https://www.nature.com/reprints/permission-requests.html">https://www.nature.com/reprints/permission-requests.html</a>). Jostins, L., et al. (2012) Host-microbe interactions have shaped the genetic architecture of inflammatory bowel disease. Nature, 491, 119-24. PMID: <a href="https://www.ncbi.nlm.nih.gov/pubmed/23128233">23128233</a>.

NIDDK IBD Genetics Consortium Repository Immunochip