Suppression of production of mouse 28S ribosomal RNA in mouse-human hybrids segregating mouse chromosomes.

Abstract
Mouse-human somatic cell hybrids that lose (segregate) human chromosomes produce only mouse 28S rRNA even when they retain copies of the human chromosomes that contain the genes for 28S rRNA. In contrast, mouse-human hybrid cells that segregate mouse chromosomes produce only human 28S rRNA even when they have retained copies of mouse chromosomes that contain the 28S rRNA genes.