Factors affecting the displacement of human chromosomes from the metaphase plate.

In order to elucidate some of the factors influencing the attachment of chromosomes to spindles, an analysis was made of the displacement of chromosomes from the metaphase plate in preparations that received no colchicine or hypotonic treatment. Displaced chromosomes were identified by Giemsa banding. Three hypotheses were tested and led to the following conclusions: (1) Chromosomal displacement is a function of size--smaller chromosomes are displaced more often than larger ones. (2) The position of the centromere does not influence chromosome displacement. (3) The amount of centromeric heterochromatin in the chromosome has a highly significant effect on displacement--chromosomes with more heterochromatin are displaced more often than those with less.