 Specific cytogenetic abnormalities can be found in many people with AML ; the types of chromosomal abnormalities often have prognostic significance . The chromosomal <unk> encode abnormal fusion proteins , usually transcription factors whose altered properties may cause the " differentiation arrest " . For example , in acute promyelocytic leukemia , the t ( 15 ; 17 ) translocation produces a PML @-@ <unk> fusion protein which binds to the <unk> acid receptor element in the <unk> of several myeloid @-@ specific genes and inhibits myeloid differentiation . 
