Flow karyotyping

Hashimoto, K. (1992) Flow karyotyping and chromosome sorting. Nippon Rinsho. 50,2484-2488. 

Milan, D., Yerle, M., Schmitz, A., Chaput, B., Vaiman, M., Frelat, G., and Gellin, J. (1993) A PCR-based method to amplify DNA with random primers determining the chromosomal content of porcine flow-karyotype peaks by chromosome painting. Cytogenet. Cell Genet. 62,139-141. 

Figure 8.20 shows examples of flow karyotypes from different... 

Fig. 8.19. A flow karyotype (fluorescence histogram) of Chinese hamster chromosomes stained with propidium iodide (PI). The G-banded chromosomes from this particular aneuploid cell line are included for comparison with the histogram peaks. From Cram et al. (1988).

Fig. 8.20. Flow karyotypes from human chromosomes (A), hamster chromosomes (B), and mouse chromosomes (C). From Gray and Cram (1990).

There has been much discussion about the potential utility of flow cytometry of chromosomes for clinical diagnosis. As regards its sensitivity, this technique appears to stand somewhere between the technique of flow analysis of whole cells for DNA content and that of microscope analysis of banded chromosomes. It may be a useful intellectual exercise for readers to ask themselves which technique or techniques would be most appropriate for detecting the following types of chromosome abnormalities (1) tetraploidy, where the normal chromosome content of cells is exactly doubled because of failure of cytokinesis after mitosis (2) an inversion in an arm of one particular chromosome and (3) trisomy (the existence of cells with three instead of two) of one of the small chromosomes. In addition to these limitations, the use of flow cytometry to look for abnormal chromosomes has been confounded by the fact that several human chromosomes are highly polymorphic, and flow karyotypes, therefore, vary considerably among normal individuals. 

Fig. 8.20. Reprinted with permission of John Wiley Sons, Inc. 1990 from Gray JW and Cram LS (1990). Flow karyotyping and chromosome sorting. Melamed MR, et al. (eds). Flow Cytometry and Sorting. New York Wiley-Liss, pp 503-529. The work was performed at the University of California Lawrence Livermore National Laboratory under the auspices of the U.S. Department of Energy.

Gray JW, Cram LS (1990) Flow karyotyping and chromosome sorting. In Melamed MR, Lindmo T, Mendelsohn M (eds) Flow cytometry and sorting. Wiley-Liss, New York, pp 503-530... 

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