New selective Giemsa technique for human chromosomes, C_d staining

Abstract

AFTER the introduction of the quinacrine fluorescence method¹, several Giemsa staining techniques have been developed for karyotype analysis of human chromosomes. Pardue and Gall², originally noticed a denser staining of centromeric regions of chromosomes after in situ hybridisation of mouse chromosome preparations with mouse satellite DNA followed by Giemsa staining. This initial approach was modified by Arrighi and Hsu³ who omitted DNA hybridisation. Later, Sumner et al.⁴ left out treatment with RNase and HC1 as well. Finally, McKenzie and Lubs⁵ treated chromosomes with HCl and 2×SSC only. These modified Giemsa procedures all produce densely stained regions of one or both chromosome arms close to the centromere. These C-band procedures also stain the secondary constriction of chromosome 1, 9 and 16, as well as the distal part of the Y chromosome. Satellites that stain brightly by Q-band techniques are also revealed by these methods.