Six patients with NS and Noonan-related disorders and one with CS had reported gene mutations, including PTPN11 in 2 patients (P1 and P2), RAF1 in 2 patients (P3 and P4), BRAF in 1 patient (P5), SHOC2 in 1 patient (P6) and HRAS in 1 patient (P9). Here, HRAS is linked to Cowden syndrome 1.