Prader–Willi syndrome (PWS), which is also associated with a depletion of hypothalamic oxytocin producing neurons [132] as well as a reduction in the peripheral expression of the OXTR in humans [133], presents with hyperphagia, lack of satiety, obesity, hypotonia, and unfavorable body composition [134]. Here, OXTR is linked to obesity due to melanocortin 4 receptor deficiency.