The Type 1 Diabetes Genetics Consortium (T1DGC).

Type 1 diabetes results from the autoimmune destruction of the insulin-producing beta cells. Genetic factors account for ∼50% of the risk for type 1 diabetes but, by the late 1990's, the genetic basis was limited. The Type 1 Diabetes Genetics Consortium (T1DGC) was formed in 2002 to accelerate discovery of genes contributing to type 1 diabetes risk through a grant from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) to assemble existing data and samples from affected sib-pair families and to establish new collections. In recognition of the 75th anniversary of the NIDDK, this manuscript highlights the contributions made by the T1DGC to understanding the genetic basis of type 1 diabetes using both family (for linkage) and case-control (for genome-wide association) designs. The T1DGC conducted large-scale genetic research and used fine mapping to define risk regions. The T1DGC data, results, and samples have been made available to the scientific community, leading to the discovery of over 100 loci associated with type 1 diabetes risk, many with small effects and relevant to autoimmune pathways. The T1DGC not only expanded the list of genes contributing to disease risk but also identified non-coding genetic variation in disease-relevant cell types that contributed to the etiology of type 1 diabetes. The success of the T1DGC and the NIDDK investment in the global consortium is highlighted in its continuing impact on mapping genetic variants to their function and identifying pathways that provide new targets for prediction, prevention and treatment of type 1 diabetes.