The Genetics of Obesity Study (GOOS) cohort consists of over 3000 patients ascertained for severe obesity, defined as a BMI ≥ 4 SDs above the age- and sex-specific mean, and onset of obesity before 10 years of age. In this study, we selected a discovery set of 1000 UK Caucasian patients from this cohort in whom developmental delay had been excluded by routine clinical examination by experienced Physicians (this cohort is referred to as SCOOP). Mutations in LEPR, POMC and MC4R were excluded by direct nucleotide sequencing and a karyotype was performed. DNA samples were analysed using Affymetrix Genome-Wide Human SNP Array 6.0 by Aros, Inc (Århus, Denmark), of which 931 passed quality control.
