title: Paralogous origin of the red- and green-sensitive visual pigment genes in vertebrates.
abstract: The nucleotide sequence of the red-sensitive visual pigment gene, R007Af, in the fish Astyanax fasciatus, from the initiation codon to the stop codon of this gene, including introns, is 1,592 bp, making it the shortest visual pigment gene known in vertebrates. Analysis of this and other homologous sequence data suggests that vertebrates initially had two duplicate genes and that each ancestor of Astyanax, human, and chicken independently duplicated the gene in the process of developing their red-green color vision. Furthermore, many extant red-green colorblind organisms may be explained simply by the failure of achieving very specific nucleotide substitutions at the three codon positions 180, 277, and 285, rather than by the lack of duplicate loci.
authors.affiliation: Department of Biology, Syracuse University, New York 13244.
authors.forename: S
authors.initials: S
authors.lastname: Yokoyama
authors.forename: W T
authors.initials: WT
authors.lastname: Starmer
authors.forename: R
authors.initials: R
authors.lastname: Yokoyama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D002645:Chickens / Q000235:genetics; D003118:Color Perception / Q000235:genetics*; D004247:DNA / Q000302:isolation & purification; D005091:Exons; D005399:Fishes / Q000235:genetics; D014644:Genetic Variation; D015186:Hominidae / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D009838:Oligodeoxyribonucleotides; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012168:Retinal Pigments / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D014714:Vertebrates / Q000235:genetics*
chemical_list: D009838:Oligodeoxyribonucleotides; D012168:Retinal Pigments; D004247:DNA