Fins and Furs - a Look at the Importance of the Zebra Fish in DNA Testing

For the past few years, the zebra fish has become a more common animal used in genetics testing. The zebra fish shares many features with a model organism. A model organism is cheap so that the testing can stay under budget, and it has short generation times so there is no long waiting for the anime to grow up. Model organisms are also easy to manipulate so a scientist working with one will be able to modify the organism to fit the experiment. Common model organisms these days are yeast (used for unicellular research), fruit flies (used more for general multicultural research), zebra fish (great for testing for vertebrates), mice (used in mammalian experiments), and humans. Zebra fish specifically are great models because they are small, grow quickly, reproduce quickly, and have transparent embryos which help scientists study the development of the young creatures more easily. Similarities between the Zebra fish and humans make it ideal for testing certain types of genetic diseases for example testing the ear of a zebra fish to discover something about the ear of a human. Dr. Burgess, working with the National Human Genome Research, has been studying the ears of zebra fish to better grasp which genes determine how a human ear is affected. Because the genetic codes are so similar between humans and zebra fish anyway, there are few differences in the ears as well. Although the ears of a fish are inside its head, they still can hear and they work the same way as a human's ear.

Once the sequence of breeding mutations of a zebra fish is finished, there are some fish that end up deaf in a sense. A simple way to test if the fish actually can hear is to tap on the glass of a fish tank. If the fish can hear the tap then they will scatter away leaving behind the fish that are unmoved because they could not hear the tap. The flaw in this method is that some fish won't swim away because they can't; most fish at this stage of development for the mutated generation have serious distortions possibly crippling their ability to swim.

A way around this is to poke the fish that do not swim away from the tapping, if these fish then swim away then they are deaf fish. As soon as a deaf fish is found, tests are run to map out its DNA and determine which gene caused its ability to hear to mutate. Another alternative is that a zebra fish will end up with many small ears as opposed to one normal sized ear, but the small ears won't work at all so the fish is deaf. Genetic diseases that cause deafness in humans might be present in the genes of zebra fish. In total, scientists use other animal's genes to study human genetics. In the future other animals that relate even closer to humans will be used as means of studying human genetics.