The major syndromes can be categorized into the following three groups: those without preexisting disease or organ dysfunction [e.g., DDX41, tumor protein p53 (TP53), and CEBPA], those with pre-existing platelet disorders [e.g., ANKRD26, ETV6, and RUNX1], and those with organ dysfunction [e.g., SAMD9/SAMD9L, GATA2, and inherited bone marrow failure syndromes (IBMFSs)]. The gene discussed is RUNX1; the disease is blood platelet disease.