JAK2 and myeloid neoplasm: The genes altered in myeloid malignancies encode proteins that regulate a broad array of functions, such as signaling pathway proteins [e.g., fms-like tyrosine kinase 3 (FLT3) and Janus kinase 2 (JAK2)]; transcription factors [e.g., CCAAT enhancer-binding protein alpha (CEBPA), runt-related transcription factor 1 (RUNX1)]; tumor suppressor proteins [e.g., tumor protein p53 (TP53)]; and spliceosome components (e.g., splicing factor 3B subunit 1 (SF3B1)).