HRAS and Noonan syndrome: Given the clinical symptoms of patients from which the missense mutations studied here were identified (as shown in Figure 5E, all the H-Ras mutations are associated with Costello syndrome (CS); most of the Raf-1 mutations are associated with Noonan syndrome (NS); most of the B-Raf and all of the Mek mutations are associated with cardio-facio-cutaneous syndrome (CFCS)), the result in Figure 5A–5D suggests that NS and CFCS may share some degree of similarity in terms of disease development.