The top five most prevalent gene mutations in AML were NRAS (23%), CEBPA (19%), FLT3-ITD (16%), NPM1 (15%), and DNMT3A (14%); in MDS they were U2AF1 (18%), TET2 (16%), ASXL1 (16%), DNMT3A (13%), and SF3B1 (12%); in MDS/MPN they were NRAS (25%), ASXL1 (22%), KRAS (19%), PTPN11 (17%), and SETBP1 (17%); finally, in MPN they were JAK2 (74%), ASXL1 (14%), CALR (10%), MPL (9%), and DNMT3A (7%). The gene discussed is PTPN11; the disease is myelodysplastic syndrome.