Dicentric chromosomes
Physical breakage of
the DNA molecule
in two non-homologous
chromosomes can produce "sticky
ends"
that recombine end-to-end (top right). The
ends of the chromosomes are lost as acentric
fragments. In a standard metaphase
chromosome spread, the replicated chromosomes appear as a
single
chromosome
with two centromeres.
At
mitosis, the two centromeres may segregate together to the same
pole, or segregate to
alternative poles
and produce segmental aneuploidy.