PubMed and Google scholar tools were used to retrieve relevant publications by using the following terms: Noonan syndrome, PTPN11, KRAS, SOS1, RAF1, NRAS, BRAF, MEK1, RIT1, SOS2, LZTR1, MRAS, CBL, RRAS, RRAS2, RASA2, SPRED1, growth, growth hormone, GH, GH treatment, puberty, scoliosis, cancer, tumor, brain tumor, MRI, Chiari malformation, dysembryoplastic, pilocytic, medulloblastoma, oligodendroglioma, glioneuronal, astrocytoma, glioma, ependymoma,pulmonary stenosis, and hypertrophic cardiopathy. This evidence concerns the gene GH1 and astrocytoma (excluding glioblastoma).