To study the role of HRD1 in hepatic metabolism and obesity, HRD1Alb mice and their littermate controls were placed on a HFD at the age of 6 weeks, whereas the body weights of HRD1Alb and control mice were indistinguishable (Fig. 1c). Here, SYVN1 is linked to obesity due to melanocortin 4 receptor deficiency.