Pericentric satellite DNA and molecular phylogeny in Acomys (Rodentia)

Satellite DNAs (stDNAs) of four Acomys species (spiny-mice), A. cahirinus, A. cineraceus, A. dimidiatus and A. russatus, belong to closely related seq uence families. Monomer sizes range from 338 to 364 bp. Between-species seq uence identity was from 81.0% to 97.2%. The molecular phylogeny of the sequ ences helps to clarify the taxonomy of this 'difficult' group. The A. dimid iatus genome contains about 60 000 repeats. According to the restriction pa tterns, repeats are arranged in tandem. The stDNA maps to the centromeric h eterochromatin of most autosomes, both acrocentric and metacentric, but app ears to be absent in the centromeric region of Y chromosomes. A well-conser ved centromere protein B (CENP-B) box is present in the stDNA of A. russatu s while it is degenerated in the other species.