Details of the HPFS, NHS and ARIC cohorts have been described previously6–8. The GWAS data in terms of study design, sample selection and genotyping have been detailed by Qi et al.37 for the HPFS and NHS cohorts and by Psaty et al.8 for the ARIC cohort. All three cohorts have been studied as part of the GENEVA (The Gene, Environment Association Studies) project38 and this study has benefitted by using data from this consortium that have been generated and cleaned using a common protocol. We selected 6,293 individuals (2,745 T2D cases and 3,148 controls) from the NHS and HPFS cohorts and 15,792 individuals from the ARIC cohort. All of these selected individuals were genotyped using the Affymetrix Genome-Wide Human 6.0 array.
