PTPN11 and Down syndrome: These include chronic and acute myelomonocytic leukemia (CML, AML),60,61 hypertrophic cardiomyopathy (HCM),62 Noonan and LEOPARD63,64 syndromes, and metachondromatosis.65 Regarding the involvement of SHP2 variants in hematopoietic and other organ/tissue disorders, multiple reviews are available.31,66 Here we focus on SHP2-related diseases that have skeletal manifestations.