PWS is a complex multisystem disorder, characterized by infantile lethargy and muscle hypotonia followed by hyperphagia and excess weight gain during early child-hood, mildly dysmorphic acro-facial features, kyphoscoliosis, developmental delay with learning and behavioral problems, and a variable number of hypothalamo-pituitary disorders comprising impaired GH secretion with short stature, hypogonadism, hypothyroidism (1, 2, 4, 5). Here, GH1 is linked to Prader-Willi syndrome.