It is associated with several monogenic disorders, including LEOPARD syndrome 1 (LEOPARD1) (MIM: 151100), Noonan syndrome 1 (NS1) (MIM: 163950), Juvenile myelomonocytic leukemia (JMML) (MIM: 607785), and metachondromatosis (MC) (MIM: 156250). The gene discussed is PTPN11; the disease is metachondromatosis.