A genome-wide association scan of nonsynonymous SNPs identifies a susceptibility variant for Crohn disease in ATG16L1.

Authors:
Jochen Hampe, Andre Franke, Philip Rosenstiel, Andreas Till, Markus Teuber, Klaus Huse, Mario Albrecht, Gabriele Mayr, Francisco M De La Vega, Jason Briggs, Simone Günther, Natalie J Prescott, Clive M Onnie, Robert Häsler, Bence Sipos, Ulrich R Fölsch, Thomas Lengauer, Matthias Platzer, Christopher G Mathew, Michael Krawczak, Stefan Schreiber
Year of publication:
2007
Volume:
39
Issue:
2
Issn:
1061-4036
Journal title abbreviated:
NAT GENET
Journal title long:
Nature genetics
Impact factor:
31.616
Abstract: 
We performed a genome-wide association study of 19,779 nonsynonymous SNPs in 735 individuals with Crohn disease and 368 controls. A total of 7,159 of these SNPs were informative. We followed up on all 72 SNPs with P <or= 0.01 with an allele-based disease association test in 380 independent Crohn disease trios, 498 Crohn disease singleton cases and 1,032 controls. Disease association of rs2241880 in the autophagy-related 16-like 1 gene (ATG16L1) was replicated in these samples (P = 4.0 x 10(-8)) and confirmed in a UK case-control sample (P = 0.0004). By haplotype and regression analysis, we found that marker rs2241880, a coding SNP (T300A), carries virtually all the disease risk exerted by the ATG16L1 locus. The ATG16L1 gene encodes a protein in the autophagosome pathway that processes intracellular bacteria. We found a statistically significant interaction with respect to Crohn disease risk between rs2241880 and the established CARD15 susceptibility variants (P = 0.039). Together with the lack of association between rs2241880 and ulcerative colitis (P > 0.4), these data suggest that the underlying biological process may be specific to Crohn disease.