Cytogenetics and Cell Genetics · 2008 · 118 citations · 0 references
Life SciencesCell BiologyGeneticsCancer GeneticsCytogeneticsHuman GeneticsCancer CytogeneticsChromosome AberrationsChromosome BiologyChromosome Number VariationComparative CytogeneticsMolecular CytogeneticsComparative Karyotype AnalysisCytogenetic KaryotypingKaryotype VariabilityKaryotype VariationKaryotypic AbnormalitiesMetaphase CytogeneticsMolecular KaryotypingNumerical Karyotype Abnormalities
Characteristic chromosome changes can distinguish clonally derived cell lines from those contaminated by cross‑contamination. The authors propose using a modal karyotype as a standard to identify and further individualize cell lines and their sublines. They defined each modal karyotype by analyzing 50 metaphases and constructing chromosome fingerprints. The study found that HeLa, HeLa S3, and HEp‑2 cell lines share a consistent marker chromosome composition with a stable copy number, that each modal karyotype encompasses all previously reported variants and often has equal or higher chromosome copies, that most cells within a line are karyotypically identical, and that a charted dataset allows easy comparison of chromosomal differences across cultures.
In contrast to earlier reports, this study on HeLa, HeLa S3, and HEp-2 revealed that karyotypes of each cell line are characterized by a consistent marker chromosome composition and a constant number of copies for both normal and marker chromosomes. Based on these chromosome fingerprints and an analysis of 50 metaphases, the modal karyotype of each cell line was defined. Each modal karyotype had the composite content of the previously reported karyotypes of the same cell line, and, generally, the former had the same or a higher number of copies per chromosome than the latter. This modal karyotype can be used as a standard to identify and further individualize both the cell line itself and a subline within that cell line. We have also found that many cells within each cell line have the same karyotype. Portions of numerical data are compiled in a chart format by which the extent of chromosome differences between cultures can readily be compared. Also discussed in brief are characteristic chromosome changes that may help distinguish clonally derived cell lines from lines derived by cross-contamination.