Background: Murine cell lines are working horses applied as model systems in multiple research studies in many laboratories. Nonetheless, most of them are not well characterized at the genetic level. This diagnosis holds also true for the MMT 060562 murine breast cancer cell line, also referred to as MMT060562 or MMT-060562. The aim of the study: To provide detailed cytogenetic characterization of the MMT 060562 cancer cell line. Materials and methods: The cell line was studied by molecular cytogenetics, namely by fluorescence in situ hybridization applying all murine while chromosome paints in one probe set and all chromosome-specific murine multicolor banding probe sets. Results: For this we present here the first detailed karyotype of the established in 1962 cell line, a comprehensive map of chromosomal imbalances and an in-silico translation of the results to the human genome. Surprisingly, MMT 060562 has only few chromosomal aberrations, even a cell clone without any gross chromosomal abnormalities in ~40% of the cells, and with most aberrant of four cell clones showing a dicentric dic(2;17)(A1A1), a derivative del(3)(A3C), a trisomy 6, and a derivative der(14)t(13;14)(14pter→14D1::14B→14D1::13A3→13qter). Conclusion: It could be shown, that MMT 060562 is most similar to human breast cancer of basal-like tumor type. Thus, this cell line can serve as a model for a very early breast cancer stage and thus closes a gap in the yet available cell lines.