Comparison of acrocentric associations in male and female cells. Relationship to the active nucleolar organizers.

This work deals with a computer-aided study of associations between trypsin-banded acrocentrics in different male and female samples in a total of 900 cells. In female samples, acrocentrics 21 appeared as the most frequently involved in associations, followed by chromosome 13, whereas in male samples cell associations seemed more randomly distributed in the different samples. In addition, investigations in one female subject showed a very high correlation between the frequency with which an acrocentric was found in association and the presence and size of its active rDNA genes as shown by silver staining followed by staining with acridine orange.