Comparative mapping of chicken anchor loci orthologous to genes on human chromosomes 1, 4 and 9

Comparative mapping of chicken and human genomes is described, primarily of regions corresponding to human chromosomes 1, 4 and 9. Segments of chicken orthologues of selected human genes were amplified from parental DNA of th e East Lansing backcross reference mapping population, and the two parental alleles were sequenced. In about 80% of the genes tested, sequence polymor phism was identified between reference population parental DNAs. The polymo rphism was used to design allele-specific primers with which to genotype th e backcross panel and place genes on the chicken linkage map. Thirty-seven genes were mapped which confirmed the surprisingly high level of conserved synteny between orthologous chicken and human genes. In several cases the o rder of genes in conserved syntenic groups differs between the two genomes, suggesting that there may have been more frequent intrachromosomal inversi ons as compared with interchromosomal translocations during the separate ev olution of avian and mammalian genomes.