Abstract
Somatic interphase cells from males and females with normal karyotypes and with variants of the heterochromatic regions on chromosomes 9 and Y were stained with the fluorochrome D287/170. The results showed that only 9h retained the ability to stain with D 287/170 in the interphase state, whereas 15ph and Yqh lost the specific staining pattern seen in metaphase. The number and size of the specific stained interphase bodies correlated with the ploidy of the cell population and the size of the 9h as seen in metaphase.