Below can be seen Syrian hamster chromosomes from three cells with different contraction . The chromosomes are staind with Acridine Orange after the cells had been grown for 7 hours with Brom-deoxy-Uridine in the media. The chromosomes are arranged according to Popescu et al. (1979, Cytogenet. Cell Genet. 24:53-60) and Cawood, A.H. (1981, Chromosoma 83:711-720).
It can be seen that many of the p-arms as well as most of the X and Y chromosomes are late replicating heterocromatic material, (grey areas). The heterochromatic material are seen most clearly in the cell shown in the middle.
Below are seen trypsin Giemsa banded chromosomes and telomeric bands. The telomeric bands are in situ hybridized by Terje Raudsepp.
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Below are seen NOR-bands. The NOR-bands are shown by in situ hybridized by Terje Raudsepp using a mink plasmid AG81 containing the NOR sequences. The bands exhibit quite some variation both within and between chromosome pairs, in some cells also chromosome pair No 6 have small NOR-bands. The counter stain of the chromosomes was DAPI, it stains very brightly the hetero chromatic regions of the chromosomes, see especially the p-arm of the X chromosome and the Y chromosome.
