A rare potentially life-threatening genetic endocrine disease characterised by childhood-onset hyperphagia and obesity, alveolar hypoventilation, dysautonomia (for example impaired gastrointestinal motility, abnormal cardiac rhythm, thermal dysregulation), hypothalamic dysfunction and neurobehavioural disorders. Central hypothyroidism, endocrine anomalies (for example glucocorticoid deficiency, puberty dysregulation), electrolyte imbalances (for example hypo/hypernatraemia, hypochloraemia), respiratory failure and late-onset neuroendocrine tumours may also be associated. [from SNOMEDCT_US]