In addition, according to their differentiation property, leukemia was further classified into three subtypes: AML M1, characterized by c-Kithigh immature myeloid cells without maturation; AML M2a, with granulocytic maturation (Gr-1 ≥ 30%, B220 < 30%); and AML M2b, exhibiting granulocytic maturation with B cell features (Gr-1 ≥ 30%, B220 ≥ 30%). This evidence concerns the gene PTPRC and acute myeloid leukemia.