A comparative map of the zebrafish genome.
Zebrafish mutations define the functions of hundreds of essential genes in the vertebrate genome.
Together with earlier efforts, this work raises the total number of markers scored in the mapping panel to 2119, including 1503 genes and ESTs and 616 previously characterized simple-sequence length polymorphisms. Sequence analysis of zebrafish genes mapped in this study and in prior work identified putative human orthologs for 804 zebrafish genes and ESTs. Map comparisons revealed 139 new conserved syntenies, in which two or more genes are on the same chromosome in zebrafish and human. Although some conserved syntenies are quite large, there were changes in gene order within conserved groups, apparently reflecting the relatively frequent occurrence of inversions and other intrachromosomal rearrangements since the divergence of teleost and tetrapod ancestors. Mapping of duplicate gene pairs identified segments of 20 linkage groups that may have arisen during a genome duplication that occurred early in the evolution of teleosts after the divergence of teleost and mammalian ancestors.