In order to assess the diagnostic usefulness and clinical application of molecular
biologic techniques, samples of human leukemias were analyzed by cytogenetic method
and several molecular biologic techniques.
1. In the leukemic cells of 21 patients with chronic myelogenous leukemia(CML)
Philadelphia chromosome, t(9;22), was observed in 17 cases. Three cases showed cells
containing a complex or atypical translocations involving chromosome 9. One patient in
blastic phase contained an abnormal karyotype, 45, X.
2. Philadelphia chromosome (Ph¹) positive leukemia patients showed bcr
rearrangement but in Ph1 negative chronic myelogenous leukemla patients
showed no bcr gene rearrangement. Neither rearrangement nor amplification was
detected with C-myc or N-ras in chronic myelogenous leukemia, acute myelogenous
leukemia, and acute lymphocytic leukemia.
Southern blot analysis of DNA from the blast cells of ALL patients showed
rearrangment of the immunoglobulin heavy chain gene, without evidence of
rearrangement of η or λ light chains.
3. Speficic DNA segment which was amplified through the polymerase chain
reaction(PCR) was found in cases of Ph1 positive CML or in K-562 cell
lines.

Keywords: Leukemia, Cytogenetics, Protoorcogene, Polymerase chain reaction,