title: Variation in the number of genes for rRNA among human acrocentric chromosomes: correlation with frequency of satellite association.
abstract: Grain counts after hybridization of 125I-rRNA to human chromosomes indicate numerical polymorphism at the rDNA sites. Prephotographing procedures decrease labeling but do not change the proportions of labeled RNA annealed to different chromosomes. A positive correlation was found between the frequency of participation of a given chromosome in satellite associations and its rDNA content by the criterion of grain count. Certain individual chromosomes are clear exceptions to this correlation.
mesh_terms: D000483:Alleles; D002875:Chromosomes / Q000648:ultrastructure; D002901:Chromosomes, Human, 13-15; D002902:Chromosomes, Human, 16-18; D002904:Chromosomes, Human, 21-22 and Y; D004247:DNA; D004276:DNA, Satellite; D005796:Genes; D006801:Humans; D012335:RNA, Ribosomal
chemical_list: D004276:DNA, Satellite; D012335:RNA, Ribosomal; D004247:DNA