Evolution Of Dogs Essay

Since Charles Darwin used dogs to support his legendary theory of evolution in his famous book, On The Origin Of Species, dog was the famous subject in evolutionary biology. Though Darwin believed various species of dog were domesticated from many different species of canidae family, we now know that all dogs are the descendent of the same species. However, even though human has been breeding dogs over thousand years, the details on the beginning of the dog domestication is still hazy. Authors of the paper questioned the genetic basis of the domestication of the wolf to the ancient dog breed. To study early dog domestication, authors sequenced whole-genome of four grey wolves, three Chinese indigenous dog and three modern breeds. For whole-genome sequencing, genome of four grey wolves from Russia and China and three Chinese indigenous dogs from Southwest China were collected. Also, genome of a German Shepherd, a Belgium Malinois and a Tibetan Mastiff were sequenced as a modern breed. Additionally, for the reference, Boxer genome was downloaded for subsequent analysis. Authors used Illumina’s GAIIx to sequence genomic DNA

So authors expected that the positively selected genes in dogs might overlap the positively selected genes in humans. 1,708 positively selected genes for humans and dogs were identified and 32 genes were overlapped between humans and dogs. First group of genes that overlapped involve with digestion and metabolism. While the consumption of plant material has been dramatically increased, this was expected. The genes involved in neurological processes were the second group. In the effect of parallel evolution, the dog responds to the drug that originally treats humans in similar manner. Interestingly, third group is the genes that are related to the cancer. Including the mesenchymal epithelial transition factor, many other cancer related genes showed parallel evolution between humans and