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In our first animation of this series we learned how point mutations can edit genetic information. Here we see how duplication events can dramatically lengthen the genetic code of an individual. As point mutations add up in the duplicated region across generations, entirely new genes with new functions can evolve. In the video we see three examples of gene duplications resulting in new traits for the creatures who inherit them: the evolution of a venom gene in snakes, the evolution of leaf digestion genes in monkeys, and the evolution of burrowing legs in hunting dogs.

"Thus far, the lineages of wolves that likely gave rise to dogs have not yet been discovered and it's possible that these puppies could be on that lineage, which would be very exciting," said evolutionary biologist Greger Larson, of the University of Oxford, one of the scientists behind a collaborative project aimed at finding out when and where dogs became the first domesticated animals.

Dogs are excellent models for studying genetics, especially disease genetics. Work done in the last 20 years has shown that dogs share many gene-related disorders with people. Each breed is a closed reproductive population with distinct rates of heritable diseases, which dramatically increases the odds of finding disease-related loci. In creating new dog breeds, we reduce the gene pool within those populations, and fix many alleles. This homogeneous background makes it much easier to map QTLs and perform linkage analyses

The many forms of dogs that exist today were all created through selective breeding from the dog's ancestor, the wolf. In a span of less than 10,000 years, breeders have changed traits and body shapes of dogs by artificial selection-for example, emphasizing different aspects of hunting and herding behavior.

7:00 video: This film is the first of a two part series on the evolution of new genetic information. Here we focus on Point Mutations - the simplest natural mechanisms known to increase the genetic information of a population. Our second film of the series will focus on duplication events - natural mutations that increase the total amount of genetic information of an individual. This film was produced under the guidance of molecular biologist Dr. Nicholas Casewell. http://www.lstmed.ac.uk/about/people/... Point mutations are small, natural edits in the DNA code of an individual. These edits can be passed from parent to child. Because they are mere edits, point mutations usually do not increase the total amount of information in an individual. As new information is gained, old information is lost. Point mutations do, however, increase the total amount of information within a population. In this film you will see several examples of beneficial point mutations which have enhanced a creatures abilities or even given rise to entirely new abilities. The first two examples were directly observed in bacteria by scientists in the lab. The third is a case found in domestic dogs, the last example was discovered in several species of wild animal.

In a study published Thursday in the journal Science, they report that they've pinpointed the bit of finch DNA behind the swift transition: a gene called HMGA2. In finches, HMGA2 seems to be the primary factor in beak size - like a really good group project leader, it orchestrates the expression of a number of other genes, each of which tweaks the size of the bird's beak. The same gene also appears in dogs, horses, even humans, holding sway over body size and stature.