Application of dual-color fluorescence in situ hybridization to study on deletions of derivative chromosome 9 in chronic myelogenous leukemia.

Objective To investigate the frequency of derivative chromosome 9[der(9)]deletions in patients with chronic myeloid leukemia(CML),and evaluate the value of dual-color fluorescence in situ hybridization(D-FISH)in detection of der(9)deletions.Methods During March 2002 and December 2005 bone marrow cells of 150 chronic myelogenous leukemia in Institute of Hematology Blood Diseases Hospital,CAMS PUMC,were performed by 24 h unstimulated culture,R-banding and karyotype by conventional cytogenetic analysis(CCA).Deletions of der(9)were investigated by FISH with dual-color and dual-fusion bcr-abl DNA probe in interphase cells of bone marrow.Results CCA showed typical Ph translocation in 97/124(78.23%)and variant Ph translocation in 24/124(19.35)and 19/124(15.32%)with additional chromosome aberrations.Deletions of der(9)were identified by D-FISH in 27/150(18.00%),9 of 97 patients with typical Ph translocation and 12 of 24 patients with variant Ph translocation.The frequency of deletions was significant(P0.01)between typical and variant Ph translocation patients.Conclusion Deletions are detected in about 1/5 CML patients.D-FISH can be used as a convenient,rapid and sensitive method to detect der(9)deletions in CML.