Karyotype Giemsa banding

Schwarzacher, T., Ambros, P., and Schweizer, D. (1980) Application of Giemsa banding to orchid karyotype analysis. Plant Syst. Evol. 134,293-297. 

V Fig. 3-68. Normal male karyotype using a differential Giemsa banding stain. Each of the chromosome pairs has a distinctive pattern permitting specific chromosome identification. (From R. Sparkes)... 

Fig. 7-10 Hypothetical chromosome from the karyotype of a mammalian cell. The banding pattern comes from Giemsa staining.

Presently karyotypes of human metaphase chromosomes are used to detect genetic defects like deletions or translocations, where the chromosomes are treated by the trypsin-Giemsa protocol, to produce a typical banding pattern and imaged by optical microscopy. Because of the diffraction limit in optical microscopy, even the smallest visible band contains around 1 million base pairs. Improved resolution has been demonstrated using fluorescence NSOM on the treated chromosomes compared to conventional light microscopy. 

Karyotype Cells were treated with 0,1 pg Colcemid in 20 minutes and incubated in KCl 0,075M. Following this, cells were fixed in fixative s solution (methanol acetic acid). G banding technique Slides were treated in 0,5% Trypsin and then in 5% staining Giemsa s solution in 5 minutes. The results were analyzed by Cytovision, Nikon 600 karyotyping analysis system. 

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