Monosomal Karyotype (MK) is defined by the presence of a single autosomal monosomy, along with at least one additional autosomal monosomy or a structural chromosome abnormality, other than those associated with defining core binding factor (CBF) Acute Myeloid Leukemia (AML) [t (8; 21) (q22; q22), inv (16) (p13.1q22)/t(16; 16) (p13.1; q22)] or acute promyelocytic leukemia [t (15; 17) (q22; q12)]. This evidence concerns the gene CEBPZ and acute myeloid leukemia.