As regards the prognostic significance of the JAK2 haplotypeGGCC_46/1 in AML cases, it was demonstrated that cases with a normal karyotype bearing the haplotypeGGCC_46/1 showed a trend towards myelomonocytic proliferation and shorter disease-free survival and overall survival compared to GGCC_46/1 non carriers; on the other hand, the haplotypeGGCC_46/1 had no impact on prognosis in the subgroup of AML with an abnormal karyotype [13,25]. The gene discussed is JAK2; the disease is acute myeloid leukemia.