New World Black Wolves

Genetic research from the Stanford University School of Medicine and the University of California, Los Angeles revealed that wolves with black pelts owe their distinctive coloration to a mutation that entered the wolf population through wolf-dog hybridisation.[15] Adolph Murie was among the first wolf biologists to speculate that the wide color variation in wolves was due to interbreeding with dogs;[16] "I suppose that some of the variability exhibited in these wolves could have resulted from crossings in the wild with dogs. Such crosses in the wild have been reported and the wolf in captivity crosses readily with dogs. Some years ago at Circle, Alaska, a wolf hung around the settlement for some time and some of the dogs were seen with it. The people thought that the wolf was a female attracted to the dogs during the breeding period. However, considerable variability is probably inherent in the species, enough perhaps to account for the variations noted in the park and in skins examined. The amount of crossing with dogs has probably not been sufficient to alter much the genetic composition of the wolf population." The Wolves of Mount McKinley by Adolph Murie, 1944, ISBN 0-295-96203-8, 978-0-295-96203-0, 238 pages In 2008, Dr. Gregory S. Barsh, a professor of genetics and pediatrics at the Stanford University School of Medicine used molecular genetic techniques to analyze DNA sequences from 150 wolves, half of them black, in Yellowstone National Park, which covers parts of Wyoming, Montana and Idaho. It was discovered that a gene mutation responsible for the protein beta-defensin 3, known as the K locus, is responsible for the black coat color in dogs.[17] After finding that the same mutation was responsible for black wolves in North America and the Italian Apennines, he set out to discover the origin of the mutation. Dr. Barsh and his colleagues concluded that the mutation arose in dogs 12,779 to 121,182 years ago, with a preferred date of 46,886 years ago after comparing large sections of wolf, dog and coyote genomes.[15] At the University of California, Los Angeles, Robert K. Wayne, a canine evolutionary biologist, stated that he believed that dogs were the first to have the mutation. He further stated that even if it originally arose in Eurasian wolves, it was passed on to dogs who, soon after their arrival, brought it to the New World and then passed it to wolves and coyotes.[18] Black wolves with recent dog ancestry tend to retain black pigment longer as they age. In genetics, a mutation is a change of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal genetic element. Mutations result from unrep ired damage to DNA or to RNA genomes (typically caused by radiation or chemical mutagens), from errors in the process of replication, or from the insertion or deletion of segments of DNA by mobile genetic elements.[1][2][3] Mutations may or may not produce discernable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes, including evolution, cancer, and the development of the immune system. Mutation can result in several different types of change in sequences; these can either have no effect, alter the product of a gene, or prevent the gene from functioning properly or completely. One study on genetic variations between different species of Drosophila suggests that if a mutation changes a protein produced by a gene, the result is likely to be harmful, with an estimated 70 percent of amino acid polymorphisms having damaging effects, and the remainder being either neutral or weakly beneficial.[4] Due to the damaging effects that mutations can have on genes, organisms have mechanisms such as DNA repair to prevent mutations. Stanford University School of Medicine is the medical school of Stanford University. It is located at Stanford University Medical Center in Stanford, California. It is the successor to the Medical College of the Pacific, founded in San Francisco in 1858 and later named Cooper Medical College. Due to this descent it ranks as the oldest medical school in the Western United States. The medical school moved to the Stanford campus near Palo Alto, California in 1959. Clinical rotations occur at several hospital sites. In addition to the Stanford University Medical Center (Stanford Hospital and Clinics) and Lucile Packard Children's Hospital, Stanford has formal affiliations with Kaiser Permanente, Santa Clara Valley Medical Center and the Palo Alto Veterans Administration. Stanford medical students also manage two free clinics: Arbor Free Clinic in Menlo Park and Pacific Free Clinic in San Jose. Stanford is a cutting-edge center for translational and biomedical research (both basic science and clinical) and emphasizes medical innovation, novel methods, discoveries, and interventions in its integrated curriculum. The School of Medicine also has a Physician Assistant (PA) program that was added in 1971, called the Primary Care Associate Program. It was one of the first accredited physician assistant programs in California. It is offered in association with Foothill College. The program has graduated more than 1,300 physician assistants since its opening. Most graduates fulfill the program's mission of serving underserved medical communities.