Reaction of human heterochromatin and euchromatin to spermine

The number of cell nuclei with X and Y chromatin and the number of nuclei with a diffuse and a coarse chromatin network were determined in diploid fibroblast cultures from persons with karyotypes of 47,XXY and 47,XYY after treatment with spermine. Spermine did not affect the number of nuclei with X and Y chromatin but led to a marked increase in the number of cells with a coarse chromatin pattern of their nucleus. After the action of spermin on peripheral blood lymphocyte cultures the number of metaphases with delayed chromosomal condensation caused by preliminary treatment with 5-bromodeoxyuridine was increased considerably, and the degree of this delay also was increased. The results indicate sensitivity of the euchromatin to the condensing action of spermine and inertia of the heterochromatin.Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 79, No. 6, pp. 98–101, June, 1975.