[Study of human chromosomes using fluorescence technics].

Abstract

Fluorescent techniques permitted us to draw up a system of banding of human chromosomes, using quinacrine derivatives. This procedure may be used to measure the density of the chromosomes. Recently, other techniques which use various fluorochromes after denaturation, have been developed. The latter, which use acridine orange, give remarkably reliable and reproducible results. These techniques are particularly useful for the analysis of structural changes in the chromosomes. Their use is illustrated by a certain number of observations where they permitted the authors to determine the type of structural change and identify the chromosomes involved. The method of constitution and significance of the fluorescent bands is very controversial. It is not clearly known whether the fluorochromes combine with DNA or with protein bound to the latter. In spite of this uncertainty, the existence of heterogeneity in the structure of the chromatids at the metaphase provides new information for the understanding of chromosome organisation.