The location of four human satellite DNAs on human chromosomes

Abstract

In situ hybridisation was carried out with 3H-cRNAs transcribed from four human satellite DNAs. The human metaphase chromosomes used were stained with quinacrine and photographed prior to hybridisation. This allowed accurate karyotyping of the autoradiographs. A method of quantitative analysis of grain distribution permitted identification of minor sites of hybridisation which could be distinguished from purely random grains. The hybridisation patterns for each of the transcribed satellite cRNAs were similar, with the C-band of chromosome 9 and the Y chromosome being the most heavily labelled sites. Other detectable sites of hybridisation were the centromeric regions of chromosomes 1, 5, 7, 10, 12, 13, 14, 15, 17, 20, 21 and 22. The cRNA transcribed from DNA satellite II, however, was the only one to hybridise to the centromere region of chromosome 16. The evolution of the human satellite DNAs and the validity of current models of satellite DNA function are discussed in the light of the present results.