title: Major histocompatibility lineages and immune gene function in teleost fishes: the road not taken.
abstract: It has become increasingly clear over the course of the past decade that the immune system genes of teleosts and tetrapods are plainly derived from common ancestral genes. The last 5 years, however, have also made it abundantly clear that in the teleost genome some of these genes are organized in a manner very different from that seen in mammals. These differences are probably the result of differences in life history traits, such as fecundancy, within each group of species when faced with an evolutionary fork in the road shortly after their divergence from each other. One group, the tetrapods, including mammals, chose a highly organized linked major histocompatibility complex, while in teleosts the major histocompatibility genes remained unlinked. In this review we will discuss the structural and functional implications of this different organization, particularly for major histocompatibility genes, but drawing on the current knowledge of some other genes for further support for the hypothesis that each group took a different road, one more traveled and one less taken.
authors.affiliation: Cell Biology and Immunology Group, Wageningen Institute of Animal Sciences, Wageningen University, Wageningen, The Netherlands. rene.stet@wur.nl
authors.forename: René J M
authors.initials: RJ
authors.lastname: Stet
authors.forename: Corine P
authors.initials: CP
authors.lastname: Kruiswijk
authors.forename: Brian
authors.initials: B
authors.lastname: Dixon
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D019143:Evolution, Molecular; D005399:Fishes / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D020440:Gene Duplication; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D008040:Genetic Linkage; D014644:Genetic Variation; D006239:Haplotypes; D015395:Histocompatibility Antigens Class I / Q000737:chemistry / Q000235:genetics; D008285:Major Histocompatibility Complex; D008969:Molecular Sequence Data; D010802:Phylogeny; D011123:Polyploidy; D017386:Sequence Homology, Amino Acid
chemical_list: D015395:Histocompatibility Antigens Class I