Complete karyotype characterization of the K562 cell line by combined application of G-banding, multiplex-fluorescence in situ hybridization, fluorescence in situ hybridization, and comparative genomic hybridization

This study combines conventional cytogenetics, fluorescence in situ hybridi zation (FISH), multiplex-FISH and comparative genomic hybridization (CGH). In applying this multimodal approach on the human leukemia cell line K562, the chromosome composition was refined in detail and compared with data fro m the literature. A hypotriploid karyotype with a modal chromosome number o f 67, and 21 unique marker chromosomes were identified. The classification of six markers was identical to published data and the composition of five further markers from the literature could be fully clarified for the first time. The composition of another five markers, which have been interpreted in divergent ways in different studies, were elucidated without doubt. Fina lly, five new markers of our study seem to have no equivalents in former st udies, very likely due to limitations of conventional cytogenetics. The com binatory application of complementary techniques as shown in this study wil l be very useful to provide the basis of a refined genotype analysis on the chromosomal level. (C) 2001 Elsevier Science Ltd. All rights reserved.