CALR and essential thrombocythemia: For instance, detecting BCR-ABL1 transcript, the causative agent of rare chronic myeloid leukemia mimicking essential thrombocytemia (ET), and JAK2, CALR, MPL mutations, which are present in three myeloproliferative neoplasms: ET, primary myelofibrosis, and polycythemia vera [101,102,103].