Mutation of PTPN11, which codes for the protein tyrosine phosphatase SHP2, is associated with two clinically related pleomorphic RASopathies (Noonan syndrome and LEOPARD syndrome), both of which are characterized by cardiovascular, craniofacial and skeletal malformations (Aoki et al., 2016). Here, PTPN11 is linked to Noonan syndrome.