Mutation - Research Article from Macmillan Science Library: Genetics

Robin Cook
This encyclopedia article consists of approximately 9 pages of information about Mutation.
This section contains 2,432 words
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Phenotypic Effects and Evolution

Mutations in the germ-line cells are heritable and provide the raw material upon which natural selection operates to produce evolution. Mutations in somatic cells, which are cells that are not germ line, are not heritable but may lead to disease in the organism possessing them.

Most mutations do not cause disease and are said to be "silent" mutations. This is for at least two reasons. First, most DNA does not code for genes, so changes in the sequence do not affect the types or amounts of protein made and there is no change in the phenotype of the organism. Second, most sexually reproducing organisms are diploid, meaning they possess two copies of every gene. Many types of mutation simply disable one copy, leaving the other intact and functional. Therefore these mutations display a recessive inheritance pattern, with no effect on phenotype unless an individual inherits...

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This section contains 2,432 words
(approx. 9 pages at 300 words per page)
Buy the Mutation Encyclopedia Article
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Macmillan Science Library: Genetics
Mutation from Macmillan Science Library: Genetics. Copyright © 2001-2006 by Macmillan Reference USA, an imprint of the Gale Group. All rights reserved.
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