The efficacy and safety profiles of GH therapy have led to the approval of GH use in many countries for the treatment of growth disorders, including GH deficiency (GHD) (3), idiopathic short stature (ISS) (3), Turner syndrome (TS), Prader-Willi syndrome (PWS), chronic renal failure (CRF), small for gestational age (SGA), and Noonan's Syndrome (4, 5). This evidence concerns the gene GH1 and Timothy syndrome.