In part, the disclosure relates to methods of treating myeloproliferative disorders by administering one or more Serum Amyloid Protein (SAP) proteins. In certain aspects, the method further comprises monitoring treatment efficacy by measuring change in mutant allele burden. In certain aspects, the disclosure relates to methods of treating myelofibrosis in patient sub-populations who carry myelofibrosis-associated mutations in some of their cells by administering an SAP protein.