Genome-wide association study and meta-analysis find that over 40 loci affect risk of type 1 diabetes

Patrick Concannon and colleagues present a type 1 diabetes genome-wide association study and meta-analysis in 7,514 cases and 9,045 reference samples, reporting 22 newly identified loci. Type 1 diabetes (T1D) is a common autoimmune disorder that arises from the action of multiple genetic and environmental risk factors. We report the findings of a genome-wide association study of T1D, combined in a meta-analysis with two previously published studies. The total sample set included 7,514 cases and 9,045 reference samples. Forty-one distinct genomic locations provided evidence for association with T1D in the meta-analysis ( P < 10 −6 ). After excluding previously reported associations, we further tested 27 regions in an independent set of 4,267 cases, 4,463 controls and 2,319 affected sib-pair (ASP) families. Of these, 18 regions were replicated ( P < 0.01; overall P < 5 × 10 −8 ) and 4 additional regions provided nominal evidence of replication ( P < 0.05). The many new candidate genes suggested by these results include IL10 , IL19 , IL20 , GLIS3 , CD69 and IL27 .