Wellcome Trust Case Control Consortium

The Wellcome Trust Case Control Consortium (abbreviated WTCCC) is a collaboration between fifty research groups in the United Kingdom in the field of human genetics. Established in 2005, the WTCCC aims to conduct genome-wide association studies (GWASs) to shed light on the genetic architecture of common human diseases.[1] The founding chairman of the consortium was University of Oxford statistician Peter Donnelly. The consortium was funded by £9 million from the Wellcome Trust.[2] According to the consortium's website, it has identified "approximately 90" new susceptibility loci for common human diseases.[3]

The consortium's initial goal was to conduct large GWASs for eight common human diseases: tuberculosis, coronary heart disease, type 1 diabetes, type 2 diabetes, rheumatoid arthritis, Crohn's disease and ulcerative colitis, bipolar disorder and hypertension. These GWASs included a total of 19,000 subjects, of whom 2,000 had one of the eight diseases and an additional 3,000 served as controls.[2] The study participants were genotyped using Affymetrix's GeneChip Human Mapping 500K Array Set, and genotype calling was conducted with the Chiamo algorithm.[4]

The results of the WTCCC's initial research were reported in Nature in 2007. The research identified 24 genetic association "signals" that were statistically significant at P < 5 × 10⁻⁷.[5][6] At the time, this was the largest study ever conducted of the genetics of human diseases.[7] In announcing the study's findings at a London news conference, Donnelly said, "If you think of the genome as a very long road that you are trying to find your way along in the dark, previously we have only been able to turn lights on in a small number of places, but now we can turn on lights in a large number of places— in this case half a million lights".[8] The 2007 Nature paper was later named "paper of the year" by the Lancet,[9] and it led to the WTCCC being named "research leader of the year" by Scientific American.[10]