Related topics: proceedings of the national academy of sciences , genes , breast cancer
Mutation
hideIn biology, mutations are changes to the nucleotide sequence of the genetic material of an organism. Mutations can be caused by copying errors in the genetic material during cell division, by exposure to ultraviolet or ionizing radiation, chemical mutagens, or viruses, or can be induced by the organism itself, by cellular processes such as hypermutation. In multicellular organisms with dedicated reproductive cells, mutations can be subdivided into germ line mutations, which can be passed on to descendants through the reproductive cells, and somatic mutations, which involve cells outside the dedicated reproductive group and which are not usually transmitted to descendants. If the organism can reproduce asexually through mechanisms such as cuttings or budding the distinction can become blurred. For example, plants can sometimes transmit somatic mutations to their descendants asexually or sexually where flower buds develop in somatically mutated parts of plants. A new mutation that was not inherited from either parent is called a de novo mutation. The source of the mutation is unrelated to the consequence, although the consequences are related to which cells were mutated.
Mutations create variation within the gene pool. Less favorable (or deleterious) mutations can be reduced in frequency in the gene pool by natural selection, while more favorable (beneficial or advantageous) mutations may accumulate and result in adaptive evolutionary changes. For example, a butterfly may produce offspring with new mutations. The majority of these mutations will have no effect; but one might change the color of one of the butterfly's offspring, making it harder (or easier) for predators to see. If this color change is advantageous, the chance of this butterfly surviving and producing its own offspring are a little better, and over time the number of butterflies with this mutation may form a larger percentage of the population.
Neutral mutations are defined as mutations whose effects do not influence the fitness of an individual. These can accumulate over time due to genetic drift. It is believed that the overwhelming majority of mutations have no significant effect on an organism's fitness. Also, DNA repair mechanisms are able to mend most changes before they become permanent mutations, and many organisms have mechanisms for eliminating otherwise permanently mutated somatic cells.
Mutation is generally accepted by the scientific community as the mechanism upon which natural selection acts, providing the advantageous new traits that survive and multiply in offspring or disadvantageous traits that die out with weaker organisms.
For more information about Mutation, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with gene mutation
Scientists take important step toward the proverbial fountain of youth
Dec 22, 2009 |
4.7 / 5 (7) |
0
Going back for a second dessert after your holiday meal might not be the best strategy for living a long, cancer-free life say researchers from the University of Alabama at Birmingham. That's because they've shown exactly ...
Search results for gene mutation
Adding a genetic supertool: Genome Analyzer fuels research dreams and tomorrow's cures
Dec 22, 2009 |
5 / 5 (1) |
0
To identify the hemophilia mutation that affected Queen Victoria and her European relatives, scientific detectives used a cutting-edge "deep sequencing tool." Able to trace rare genetic disease mutations, the tool can turn ...
What is the function of the protein CD20?
Dec 22, 2009 |
not rated yet |
0
Antibodies directed against the protein CD20, which is expressed by immune cells known as B cells, are used to treat B cell non-Hodgkin lymphoma and rheumatoid arthritis. Despite this, the function of CD20 has not been determined. ...
Gene therapy makes mice breath easier
Dec 21, 2009 |
5 / 5 (1) |
0
Researchers from Boston University School of Medicine (BUSM) have discovered a new gene therapy that may prevent the progression of emphysema. The study, which appears on-line in the Journal of Clinical Investigation, descri ...
Gefitinib improves survival compared with standard chemotherapy in lung cancer patients with genetic mutation
Dec 20, 2009 |
5 / 5 (1) |
0
Patients with the most common form of lung cancer (non-small-cell lung cancer) who have mutations in the epidermal growth factor receptor (EGFR) gene have significantly improved progression-free survival if they are treated ...
Mutation leads to new and severe form of bacterial disease
Dec 18, 2009 |
not rated yet |
0
(PhysOrg.com) -- Everybody gets sick, but how sick you get is in your genes. New research now reveals a mutation on a gene that makes children susceptible to a severe form of mycobacterial disease. The work not only supports ...
Research suggests link between infertility, low egg reserve, and breast/ovarian cancer gene (BRCA1)
Dec 18, 2009 |
not rated yet |
0
A New York Medical College physician who specializes in restoring or preserving fertility in female cancer patients has discovered a possible link between the presence of breast cancer genes and infertility.
Lung cancer and melanoma laid bare: First comprehensive analysis of two cancer genomes
Dec 16, 2009 |
5 / 5 (4) |
0
Research teams led by the Wellcome Trust Sanger Institute announce the first comprehensive analyses of cancer genomes. All cancers are caused by mutations in the DNA of cancer cells which are acquired during a person's lifetime. ...
Scientists use DNA sequencing to attack lung cancer
Dec 16, 2009 |
5 / 5 (1) |
0
Aided by next-generation DNA sequencing technology, an international team of researchers has gained insights into how more than 60 carcinogens associated with cigarette smoke bind to and chemically modify human DNA, ultimately ...
Gene identified as cause of some forms of intellectual disability
Dec 15, 2009 |
not rated yet |
0
A gene involved in some forms of intellectual disability has been identified by scientists at the Centre for Addiction and Mental Health (CAMH), as published this month in The American Journal of Human Genetics. The gene i ...
Discovery of new gene called Brd2 that regulates obesity and diabetes
Dec 15, 2009 |
4.5 / 5 (2) |
0
The chance discovery of a genetic mutation that makes mice enormously fat but protects them from diabetes has given researchers at Boston University School of Medicine, USA, new insights into the cellular mechanisms that ...
List of search results for gene mutation
