Origin of the domestic dog to the domestic dog and modern wolf lineages. The gray wolf is thought to be ancestral to the domestic dog, however its relationship to "C. variabilis", and the genetic contribution of "C. variabilis" to the dog, is the subject of debate. The Zhokhov Island (8,700 YBP) and Aachim (1,700 YBP) canid haplotypes fell within the domestic dog clade, cluster with S805, and also share their haplotypes with – or are one mutation away from – the Tibetan wolf ("C. l. chanco") and the recently-extinct Japanese wolf ("C. l. hodophilax"). This may indicate that these canids retained the genetic signature of
Origin of the domestic dog initial domestication and then later in breed formation. In 2018, a study identified 429 genes that differed between modern dogs and modern wolves. As the differences in these genes could also be found in ancient dog fossils, these were regarded as being the result of the initial domestication and not from recent breed formation. These genes are linked to neural crest and central nervous system development. These genes affect embryogenesis and can confer tameness, smaller jaws, floppy ears, and diminished craniofacial development, which distinguish domesticated dogs from wolves and are considered to reflect domestication syndrome. The study proposes that domestication