慢性髓性白血病的髓细胞在染色体组型上有典型的费城染色体，22号染色体的q臂的一部分与9号染色体q臂的一部分易位，定义为t（9：22)。
Myeloid cells of CML are also characterized by the Philadelphia chromosome (Ph1) on karyotyping. This is a translocation of a portion of the q arm of chromosome 22 to the q arm of chromosome 9, designated t(9:22).
