The original association between this GSV and obesity was supported by reported disproportionate extreme hyperinsulinaemia in carriers of the deletion [10]. We sought to confirm this finding by investigating fasting insulin and the response to oral glucose in the subjects from our study. However, we found no evidence in our cohorts for the reported phenotype. Compared to the remainder of the cohort from which they were drawn, levels of fasting insulin in carriers of the deletion were not discernibly different from those expected for a subject’s BMI, for both children (Fig. 2a) and adults (Fig. 2b), with no indication of the reported 3-fold increase; similar conclusions were drawn when the comparison was limited to individuals of the same gender and age (Figure S2). Equally, no difference was observed in either fasting insulin (Fig. 2b) or in the insulin response to oral glucose (Fig. 2c) between carrier and non-carrier parents of child probands.
