To further question the implication of JAG2 in adiposity, we studied its expression in liver and white adipose of two independent mice models contrasted for adiposity: B6.V-Lepob/J mice (n = 8), which are KO for the gene encoding leptin and have severe obesity compared with mice from the same genetic background C57BL6/J (n = 8), and the Hybrid Mouse Diversity Panel (Bennett et al. 2010; Ghazalpour et al. 2012), which includes a population of 96 inbred mouse strains variable for obesity-related phenotypes, including total body fat mass. Here, JAG2 is linked to obesity due to melanocortin 4 receptor deficiency.