Quinacrine, chromosome staining

The packaging of nucleoproteins within chromatids is not random, as evidenced by the characteristic patterns observed when chromosomes are stained with specific dyes such as quinacrine or Giemsa s stain (Figure 36-6). 

Kapp et al. (1979) reported the presence of Y-chromosomal non-disjunction in 1,2-dibromo-3-chloropropane-cxposed workers using a quinacrine-staining technique. [There was no indication of the level of exposure to 1,2-dibromo-3-chloropropane or whether other exposures were present.] The frequency of sperm with two spots (indicating two Y chromosomes) was 1.2% (range, 0.8-1.8%) in 15 controls and 3.8% (range, 2.0-5.3%) in 18 samples from exposed men. 

Ellison J.R. and Barr H.J. 1971. Differences in the quinacrine staining of the chromosomes of a pair of sibling species Drosophila melanogaster and Drosophila simtdans. Chromosoma 44 424—435. 

Rowley JD. Tetter A new consistent chromosomal abnormality in chronic myelogenous leukaemia identified by quinacrine fluorescence and Giemsa staining. Nature 1973 243 290-293. 

Karyotyping has advanced dramatically since it was discovered that certain stains stain individual chromosomes in characteristic ways. Caspersson (Caspersson et al., 1970a,b, 1971) showed that quinacrine mustard and quinacrine dihydrochloride (Fig. 7.7) produced a characteristic banding pattern (Q-banding), and later it was found that complementary bands could be formed with Giesma (G-bands) if the chromosomes are treated first with trypsin or mild alkali (Patil et al., 1971 Seabright, 1971 Wang and Federoff, 1972). 

Another property of such dyes is observed when they are used to stain metaphase chromosomes. When these dyes bind to chromosomal DNA, some parts of the chromosome fluoresce stronger than others giving a typical and reproducible fluorescence pattern. These fluorescence are used for chromosome analysis and identification. Andreoni et al.48 50) investigated the fluorescence decay of in band and out of band parts in Vicia fabia chromosomes stained with quinacrine mustards. They used a microbeam system (Chapter 3) with a nitrogen laser pumped dye laser. Their results seem to suggest that the band considered was to be attributed mainly to a higher dye concentration inside than outside the band. 

Caspersson T., Castleman K.R., Lomakka G., Modest E.J., Moller A., Nathan R., Wall R.J., Zech L. (1971). Automatic karyotyping of quinacrine mustard stained human chromosomes. Exp. Cell Res. 67 233-235. 

Weisblum B. and de Haseth P.L. (1972). Quinacrine, a chromosome stain specific for deoxyadenylate-deoxythymidylaterich regions in DNA. Proc. Natl. Acad. Sci. USA 69 629-632. 

Fortunately, in the early1970 s, two relatively simple staining methods were developed which permitted unequivocal identification of each chromosome a method using a quinacrine fluorescent stain and another using the familial Giemsa stains [222]. 

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