INS and obesity due to melanocortin 4 receptor deficiency: To allow for a particular variant to be associated with several clusters, Udler et al applied ‘soft clustering’ to 95 type 2 diabetes loci (associated with 47 diabetes-related traits) and identified five robust clusters, two related to insulin secretion (‘beta cell’ and ‘proinsulin’) and three to insulin response or action (‘obesity’, ‘lipodystrophy’ and ‘liver/lipid’) [87].