Chromosome homologies between man and mountain zebra (Equus zebra hartmannae)and description of a new ancestral synteny involving sequences homologous to human chromosomes 4 and 8

Using human chromosome painting probes, we looked for homologies between hu man and mountain zebra (Equus zebra hartmannae, Equidae, Perissodactyla) ka ryotypes. Except for two very short segments, all euchromatic regions were found to have a human homologous chromosome segment. Conserved syntenies pr eviously described in various mammalian orders were detected. Each synteny corresponded to a chromosomal region homologous to two parts of human chrom osomes: HSA3 and HSA21, HSA7 and HSA16, HSA12 and HSA22, and HSA16 and HSA1 9. Chromosomal segments homologous to a part of HSA11 and HSA19p are found syntenic in zebra, horse and donkey, suggesting that this group of synteny has been inherited from an Equidae or Perissodactyla common ancestor. A syn teny of segments homologous to parts of HSA4 and HSA8 was observed in zebra and horse. It also exists in the rabbit (Lagomorpha) and several Carnivora species. A second group of taxa which does not have this region of synteny is composed of primates, Chiroptera and Insectivora, and possibly also Cet acea and Scandantia. Thus, the presence or absence of this region of synten y may separate two groups of eutherian mammals. Copyright (C) 2001 S. Karge r AG, Basel.