Conservation Genetics

, Volume 3, Issue 1, pp 29–43 | Cite as

Detecting rare introgression of domestic dog genes into wild wolf (Canis lupus) populations by Bayesian admixture analyses of microsatellite variation

  • Ettore RandiEmail author
  • Vittorio Lucchini


Hybridization with free-ranging dogs isthought to threat the genetic integrity ofwolves in Europe, although available mtDNA dataevidenced only sporadic cases of crossbreeding.Here we report results of population assignmentand genetic admixture analyses in 107wild-living Italian wolves, 95 dogs including30 different breeds and feral dogs, andcaptive-reared wolves of unknown or hybridorigins, which were genotyped at 18microsatellites. Two Italian wolves showedunusually dark coats (``black wolves''), and oneshowed a spur in both hindlegs (``fifth fingerwolf''), suggesting hybridization. Italianwolves showed significant deficit ofheterozygotes, positive FIS values anddeviations from Hardy-Weinberg equilibrium.Genetic variability was significantlypartitioned between groups, suggesting thatwolves and dogs represent distinct gene pools.Multivariate ordination of individual genotypesand clustering of inter-individual geneticdistances split wolves and dogs into twodifferent clusters congruent with the priorphenotypic classification, but hybrids andwolves of unknown origin were not identifiedfrom genetic information alone. By contrast, aBayesian admixture analysis assigned all theItalian wolves and dogs to two differentclusters, independent of any prior phenotypicinformation, and simultaneously detected theadmixed gene composition of the hybrids, whichwere assigned to more than one cluster.Captive-reared wolves of unknown origin wereprevalently assigned to the Italian wolfpopulation. Admixture analyses showed that one``black wolf'' had mixed ancestry in the dog genepool and could be a hybrid, while the other twowolves with unusual phenotypes were assigned tothe Italian wolf population.

admixture analysis assignment test Bayesian clustering Canis lupus dog wolf 


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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  1. 1.Istituto Nazionale per la Fauna SelvaticaOzzano dell'Emilia (BO)Italy

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