title: Genetic analysis of cavefish reveals molecular convergence in the evolution of albinism.
abstract: The genetic basis of vertebrate morphological evolution has traditionally been very difficult to examine in naturally occurring populations. Here we describe the generation of a genome-wide linkage map to allow quantitative trait analysis of evolutionarily derived morphologies in the Mexican cave tetra, a species that has, in a series of independent caves, repeatedly evolved specialized characteristics adapted to a unique and well-studied ecological environment. We focused on the trait of albinism and discovered that it is linked to Oca2, a known pigmentation gene, in two cave populations. We found different deletions in Oca2 in each population and, using a cell-based assay, showed that both cause loss of function of the corresponding protein, OCA2. Thus, the two cave populations evolved albinism independently, through similar mutational events.
authors.affiliation: Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Meredith E
authors.initials: ME
authors.lastname: Protas
authors.forename: Candace
authors.initials: C
authors.lastname: Hersey
authors.forename: Dawn
authors.initials: D
authors.lastname: Kochanek
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Horst
authors.initials: H
authors.lastname: Wilkens
authors.forename: William R
authors.initials: WR
authors.lastname: Jeffery
authors.forename: Leonard I
authors.initials: LI
authors.lastname: Zon
authors.forename: Richard
authors.initials: R
authors.lastname: Borowsky
authors.forename: Clifford J
authors.initials: CJ
authors.lastname: Tabin
mesh_terms: D000417:Albinism / Q000235:genetics*; D000818:Animals; D002460:Cell Line; D003433:Crosses, Genetic; D019143:Evolution, Molecular; D005091:Exons; D005260:Female; D029941:Fish Proteins / Q000235:genetics; D005399:Fishes / Q000235:genetics* / Q000502:physiology; D005828:Genetics, Population; D015810:Linkage Disequilibrium; D008297:Male; D008544:Melanocytes / Q000166:cytology / Q000502:physiology; D051379:Mice; D008969:Molecular Sequence Data; D010858:Pigmentation / Q000235:genetics*; D011110:Polymorphism, Genetic; D040641:Quantitative Trait Loci
chemical_list: D029941:Fish Proteins