RAPGEF3 and obesity due to melanocortin 4 receptor deficiency: Alternatively, ex vivo activation of EPAC1 in iPSC-derived autologous human brown/beige preadipocytes might be a way to enhance transplantation-based approaches to increase BAT mass and, consequently, energy expenditure and/or the release of protective endocrine factors (BATokines)42 to combat diabetes and obesity.