Re-analysis of the cell line NALM-1 karyotype by GTG-banding, spectral karyotyping, and whole chromosome painting.

Chronic myelogenous leukemia (CML) is a clonal bone marrow disease with progression from a chronic phase to an aggressive blast crisis. The cell line NALM-1 was originally established by Minowada and coworkers from the peripheral blood of a patient in CML blastic crisis. A karyotype analysis of the NALM-1 cell line was performed in the 1970s. To the best of our knowledge, this karyotype was not re-analyzed by molecular cytogenetic techniques, although this cell line is the source of many molecular investigations including expression studies. To establish this cell line as a CML control in our own laboratory, NALM-1 was analyzed by GTG banding, fluorescence in situ hybridization, and spectral karyotyping. Our results differ from the original publication of Sonta and coworkers. We describe for the first time the karyotype of the NALM-1 cell line: 44,X,-X,der(7)t(7;9;15)(q10;?;q15),der(9)t(9;9)(p24;q33 approximately q34)t(9;22)(q34;q11),der(15)t(7;9;15) (?;?;q15),der(22)t(9;22)(q34;q11).