Many clinically relevant mutations have been identified in RASopathies with missense mutation in protein tyrosine phosphatase, with non-receptor type 11 (PTPN11) reported in nearly 50% of Noonan syndrome patients [39] and up to 65% of patients who later develop HCM harboring gain-of-function mutations in RAF1 [39,40,41]. The gene discussed is PTPN11; the disease is Noonan syndrome.