JAK2 and B-cell chronic lymphocytic leukemia: These potentially include patients with fusions of JAK2 with PCM1, ETV6 and BCR [44], T-cell large granular lymphocytic leukaemia [45], chronic lympho-proliferative disorders of natural killer cells [46], Waldenstrom’s Macroglobulinaemia [47], chronic myeloid leukaemia [48] and chronic lymphocytic leukaemia [49].