Researchers from Ilia State University in Tbilisi, Georgia, studying populations of wolves living alongside livestock guarding dogs (Caucasian or Georgian shepherds) in the Caucasus found that approximately 10 percent of dogs had detectable wolf ancestry, and about 13% of the wolves had detectable dog ancestry. This appears to indicate that “gene flow” (interbreeding) between the two populations used to be a relatively common event.
The study suggests that wolf x dog hybridization may have been a common event in areas where livestock guarding dogs of comparable size are used in a traditional way (i.e., running free with the flocks), and that hybridization between dogs and wolves may have exerted a force on the gene pool of both species even after the process of domestication of the dog began.
Natia Kopaliani, Maia Shakarashvili, Zurab Gurielidze, Tamar Qurkhuli and David Tarkhnishvili
Journal of Heredity (2014) 105 (3): 345-353. doi: 10.1093/jhered/esu014