Interestingly, an earlier study comparing central eCBs among racial groups found that Native Americans had more 2-AG circulating in their cerebrospinal fluid than Caucasians (116), suggesting that heightened peripheral and/or central eCB/CB1R activity in this demographic could partially account for their increased incidence of obesity and T2D. Here, CNR1 is linked to obesity due to melanocortin 4 receptor deficiency.