title: Downstairs gene flow: the effects of a linear sequence of waterfalls on the only population of the endangered minnow Astyanax xavante.
abstract: The aim of this study was to estimate the genetic diversity and structure of the only known population of minnow Astyanax xavante, which inhabits a stretch of river including several waterfalls. The FST values among the samples were not significant, except between two populations separated by a 30 m waterfall. Nevertheless, haplotype and nucleotide diversity increased in the downstream direction, indicating that gene flow is unidirectional, which indicates this genetic pattern as downstairs gene flow, as it has the effect of increasing genetic diversity in the downstream direction.
authors.affiliation: Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil.
authors.forename: K V
authors.initials: KV
authors.lastname: Reis
authors.affiliation: Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil.
authors.forename: P C
authors.initials: PC
authors.lastname: Venere
authors.affiliation: Universidade Federal do Pará, Belém, Pará, Brazil.
authors.forename: I
authors.initials: I
authors.lastname: Sampaio
authors.affiliation: Universidade Federal do Pará, Belém, Pará, Brazil.
authors.forename: P S
authors.initials: PS
authors.lastname: Rêgo
authors.affiliation: Universidade Federal do Pará, Belém, Pará, Brazil.|Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão 4485-661, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Vallinoto
authors.affiliation: Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Sala BEG313C/CCB, Florianópolis, Santa Catarina 88040-900, Brazil.
authors.forename: I L
authors.initials: IL
authors.lastname: Souza
mesh_terms: D000818:Animals; D001938:Brazil; D003530:Cyprinidae / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D056727:Endangered Species; D004777:Environment; D051456:Gene Flow; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D007438:Introns; D045483:Rivers; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial
keywords: control region; genetic diversity; mtDNA; natural barriers; unidirectional gene flow