Particularly, the Kctd15 likely acts through interaction with adipocyte protein 2 (AP-2) (Liu et al., 2013), which is a critical regulator in adipogenesis (Shan et al., 2013), suggesting a possible molecular basis for the observed associations of KCTD15 variants with obesity. This evidence concerns the gene KCTD15 and obesity due to melanocortin 4 receptor deficiency.