The type 1 cholecystokinin (CCK) receptor (CCK1R) has been identified as a potential target for drugs to treat obesity (1), one of the most prevalent and costly pathologic processes contributing to mortality and morbidity directly, as well as through co-morbidities such as diabetes mellitus and cardiovascular disease (2). Here, CCKAR is linked to obesity due to melanocortin 4 receptor deficiency.