Promyelocytic Leukemia is a type of acute myeloid leukemia, in which too many immature blood-forming cells are found in the blood and bone marrow. It is a quickly progressing disease. It was first recognized as a distinct disease in 1957. It is more commonly known as retinoic acid receptor alpha fusion protein. In case of females the hemorrhagic diathesis (bleeding condition) may precede the diagnosis of leukemia by 2-8 weeks. Creation of a promyelocytic leukemia gene is a result of the t(15;17) translocation in APL, which in turn is the result of two chromosome breaks: one in chromosome 15 and the other in chromosome 17.