SEGMENTAL HOMOLOGY AMONG CATTLE (BOS-TAURUS), INDIAN MUNTJAC (MUNTIACUS MUNTJAK VAGINALIS) AND CHINESE MUNTJAC (M-REEVESI) KARYOTYPES

In an attempt to examine homologies between Indian and Chinese muntjac karyotypes at a subchromosomal level, five bovine cosmids were compar atively mapped by heterologous fluorescence in situ hybridization (FIS H). In the Indian muntjac (2n = 6) all cosmids mapped to chromosome 1, whereas in the Chinese muntjac (2n = 46) two cosmids mapped to chromo some 3 and one cosmid each mapped to chromosomes 1, 7, and 17. These m arkers have maintained their intrachromosomal position relative to a c entromere/telomere axis in cattle and in Chinese and Indian muntjac ch romosomal arms. Our results corroborate the tandem-fusion hypothesis f or muntjac karyotypic evolution and establish orientational homology b etween the involved Chinese muntjac chromosomes and the discrete segme nts on Indian muntjac chromosome 1. Furthermore, our data disclose reg ional homologies between cattle and muntjac genomes and demonstrate th e validity of intergeneric cosmid-FISH for investigations on karyotype evolution.