WNT5A and obesity due to melanocortin 4 receptor deficiency: Our observation that Wnt5a-FKO mice fed the HFD, but not the ND, gained more fat mass than floxed mice fed the HFD (Fig. 7A–C) suggests that Wnt5a limited the over-expansion of adipose tissues, which is consistent with the finding of a previous study that identified genetic differences between an obesity-prone mouse strain (C57Bl/6 (B6)) and an obesity-resistant mouse strain (129S6/SvEvTac (129)) [52].