Drake, John W. Laboratory of Genetics, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina.
Show previous versions
- Genome or ploidy mutations
- Chromosome mutations
- Gene mutations
- Cause and prevention
- Future research
- Links to Primary Literature
- Additional Readings
An abrupt, heritable change in genes or chromosomes manifested by changes in the phenotype (appearance) of an organism. The study of mutation has long occupied a central position in genetics. Mutations (Fig. 1) are the ultimate sources of variability upon which evolution acts, despite being random changes that are far more likely to harm than to improve a complicated and highly evolved organism. Laboratory reconstructions have shown that rapidly mutating microbial populations overtake slowly mutating populations when the two are mixed and placed in a new environment to which neither is fully adapted. Mutation has consistently been the most telling probe into the nature of the gene, and the understanding of most aspects of biology has benefited from studies of the properties of mutant organisms. Mutation is also an important component of disease, either causing it directly (for example, through birth defects) or predisposing humans to a vast array of disorders that together constitute a substantial fraction of illnesses. Finally, deliberate selection of mutant plants and animals for economic or aesthetic purposes has long been practiced and has grown into an important aspect of genetics. With advances in molecular genetics, it is now possible to construct specific mutations at will, rather than merely selecting among an array of random mutations for the infrequent useful ones. See also: Breeding (animal); Breeding (plant); Chromosome; Disease; Gene; Genetics
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Its dedicated editorial team is led by Sagan Award winner John Rennie. Contributors include more than 9000 highly qualified scientists and 39 Nobel Prize winners.
MORE THAN 8500 articles and Research Reviews covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 17,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information