Some consequences of ghrelin dysregulation may be demonstrated in Prader–Willi syndrome, a neurogenetic disorder that is characterized by poor feeding and weight gain in early infancy followed by hyperphagia, impaired satiety, severe obesity, and multiple dysmorphic and psychocognitive developmental problems in childhood and adulthood. The gene discussed is GHRL; the disease is obesity due to melanocortin 4 receptor deficiency.