Genotyping was carried out using Illumina and Affymetrix genome-wide arrays,Centaurus assays (Nanogen), Taqman assays, the Sequenom MassArray iPLEX genotyping system and the Roche LightCycler480 system (Supplementary Tables 1 and 2). Quality control and imputation were performed, by study group, as described in the Supplementary Methods. Case-control or family-based association analyses were carried out for each study group. For the case-control analyses, population stratification was controlled for using genomic control or principal components. Summary statistics from the various study groups were combined as described previously15. BMI measurements were adjusted for age and sex, and inverse standard normal transformed. Analysis was carried out by regressing the adjusted, transformed data on rs4583255[T] count.
