Conservation Genetics

, Volume 10, Issue 1, pp 225–236 | Cite as

Efficiency of markers and methods for detecting hybrids and introgression in stocked populations

  • Nuria SanzEmail author
  • Rosa M. Araguas
  • Raquel Fernández
  • Manuel Vera
  • José-Luis García-Marín
Research Article


Detection of hybridization and introgression in wild populations that have been supplemented by hatchery fish is necessary during development of conservation and management strategies. Initially, allozyme data and more recently highly polymorphic microsatellite markers have been used to obtain this information. We used both markers to assess the effectiveness of four assignment methods (Structure, NewHybrids, Baps and GeneClass) to detect hatchery introgression in wild stocked populations. Simulations of hybrid genotypes from real parental data revealed that the number and type of markers used with Structure, NewHybrids and Baps can identify as admixed most first and second generation hybrids as well as first generation backcrosses. In wild populations, introgression rates estimated from different markers and methods were correlated. However, slight disagreements were observed at both population and individual levels. Overall, the fully Bayesian (Structure, NewHybrids and Baps) performed better than partially Bayesian (GeneClass) assignment tests. In wild collections, Baps analyses were limited because of the lack of a native baseline. In all cases, the efficiency of methods was reduced as introgression increased.


Allozymes Assignment methods Brown trout Introgression Microsatellites 



This research meets the objectives of the REN-2003–05931/GLO project of the Spanish MCYT. R. Fernandez and M. Vera were fellows of the Spanish MCYT. We thank FM Utter for English revision and for valuable suggestions to improve this manuscript.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Nuria Sanz
    • 1
    Email author
  • Rosa M. Araguas
    • 1
  • Raquel Fernández
    • 1
  • Manuel Vera
    • 1
  • José-Luis García-Marín
    • 1
  1. 1.Laboratori d’Ictiologia GenèticaUniversitat de GironaGironaSpain

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