<unk>  should be suspected in children or adults with distinctive physical features listed above, extremely elevated serum hGH concentrations despite low serum IGF-1 levels. A failure of IGF-1 to increase in response to exogenous hGH (IGF-1 stimulation test) is diagnostic for<unk> . The gold standard for confirming a diagnosis of<unk>  is to perform a genetic analysis with PCR to identify the precise molecular defect in the GH receptor gene. Other laboratory abnormalities include GHBP (growth hormone binding protein) levels being low in cases with mutations in the extracellular domain of the GH receptor and normal in cases with mutations in the intracellular domain. Low serum levels of IGFBP are non-diagnostic for<unk> .
Laron syndrome
Hypopituitarism
Jervell and Lange-Nielsen syndrome
STAT5B
Aagenaes syndrome
Cowden syndrome
Dennie–Marfan syndrome
Prader–Willi syndrome