Origin of the domestic dog matched across Eurasia and its branch is phylogenetically rooted in the same sequence as the Altai dog (not a direct ancestor). The subclade d2 hybrid haplotypes are found in 2.6% of South-West Asian dogs. Haplogroup E: Derived from post-domestication wolf–dog hybridization in East Asia, (rare distribution in South-East Asia, Korea and Japan). Haplogroup F: Derived from post-domestication wolf–dog hybridization in Japan. A study of 600 dog specimens found only one dog whose sequence indicated hybridization with the extinct Japanese wolf. It is not known whether this hybridization was the result of humans selecting for phenotypic traits from local wolf populations
Origin of the domestic dog 2018, a study compared sequences of fossil North American dogs with fossil Siberian dogs and modern dogs. The study indicates that dogs entered North America from Siberia 4,500 years after humans did, were isolated for 9,000 years, and after contact with Europeans these no longer exist because they were replaced with Eurasian dogs. The pre-contact dogs exhibit a unique genetic signature that is also now gone, with their nearest genetic relatives being the arctic breed dogs. In 2017, a study showed that 9,000 YBP the domestic dog was present at what is now Zhokhov Island, arctic north-eastern Siberia, which was