Evolutionary dynamics of transposable elements at the centromere.

Transposable elements are the single most abundant class of genetic material in higher eukaryotes. These elements show a genome-wide distribution but are found in disproportionate abundance at the centromeric and/or pericentric regions in a wide range of phylogenetic species. We propose at least three possible ways in which these elements could have directly contributed to the evolution of the architecture and function of the centromere in various organisms. An "extradition" mechanism also appears to have evolved, which enables the developing or established centromere to deal with the potentially disruptive effects of any subsequently arising transposable elements.