Gene Flow between Wolf and Shepherd Dog Populations in Georgia (Caucasus)

Abstract

We studied the distribution of the mitochondrial DNA haplotypes and microsatellite genotypes at 8 loci in 102 gray wolves, 57 livestock guarding dogs, and 9 mongrel dogs from Georgia (Caucasus). Most of the studied dogs had mitochondrial haplotypes clustered with presumably East Asian dog lineages, and most of the studied wolves had the haplotypes clustered with European wolves, but 20% of wolves and 37% of dogs shared the same mitochondrial haplotypes. Bayesian inference with STRUCTURE software suggested that more than 13% of the studied wolves had detectable dog ancestry and more than 10% of the dogs had detectable wolf ancestry. About 2-3% of the sampled wolves and dogs were identified, with a high probability, as first-generation hybrids. These results were supported by the relatedness analysis, which showed that 10% of wolves and 20% of dogs had closest relatives from an opposite group. The results of the study suggest that wolf-dog hybridization is a common event in the areas where large livestock guarding dogs are held in a traditional way, and that gene flow between dogs and gray wolves was an important force influencing gene pool of dogs for millennia since early domestication events. This process may have been terminated 1) in areas outside the natural range of gray wolves and 2) since very recent time, when humans started to more tightly control contacts of purebred dogs.

Complete mitochondrial genome database and standardized classification system for Canis lupus familiaris

“…The population mixing that led to "homogenization" of the dogs mtDNA gene pool could have been further augmented by migrations that took place in the past. Some evidence for hybridization between dogs and wolves was provided by analysis of entire autosomal genome variation [36], as well as by studies of haploid markers in low resolution [38,39]. Mitochondrial genome variation of wolf populations could be informative in the context of the time and place of wolf domestication.…”

The wolf reference genome sequence (Canis lupus lupus) and its implications for Canis spp. population genomics

“…Genomic and paleogenomic resources have previously been used to address major questions in domestication, including deciphering the population structure and admixture patterns in modern and wild lineages [16–18], discovering strcuture among ancient pre-domestic lineages [6, 19–22], and estimating levels of introgression from wild lineages into domesticated stocks [17, 23], applied to a multitude of species, such as maize [6, 16, 22], silkworms [24], chickens [25–27], and pig [28, 29]. …”

Wolf diet in an agricultural landscape of north-eastern Turkey

“…This enhances wolf-human encounters probability and results in increased risks of direct persecution, vehicle collisions (Fritts et al 2003) and hybridisation with dogs (Kopaliani et al 2014). Human-induced mortality cases were often reported in the study area (Chynoweth et al unpublished data), though detailed data on the wolf-livestock-human dynamics are currently lacking.…”