A genetic,deletion, physical,and human homology map of the long fin region on zebrafish linkage group 2

Mutation of the gene long fin causes overgrowth of zebrafish fins. Thus, molecular identification of the gene long fin may reveal the mechanisms involved in normal growth control. We have therefore developed genetic and physical maps of the corresponding region on linkage group 2 (LG2). A single deletion allele (lof(jg)(61)) of the long fin gene was also generated. Examination of this deletion for the presence or absence of ESTs independently mapped to LG2 revealed a contiguous deletion of SSLP, STS, and gene-based markers spanning a physical distance of approximately 500 kb, including at least 10 zebrafish genes. Human orthologs of the zebrafish genes in the long fin region were identified and revealed two synteny segments from human chromosome 1 (Hsa1) and Hsa19. Homology searching for additional genes linked to the human orthologs revealed one additional gene in the long fin deletion region. Thus, our development of the genetic, physical, deletion, and human homology maps of the long fin region provides one of the first high-resolution comparisons of a zebrafish region with a homologous human region, and facilitates the molecular identification of the long fin gene.