Mutations
Mutations
Mutations (/mjuːˈteɪʃən/; from Latin mutatio, a changing) are changes in the DNA sequence of a cell's genome. They are caused by radiation, viruses, transposons and mutagenic chemicals, as well as errors that occur during meiosis or DNA replication. They can also be induced by the organism itself, by cellular processes such as hypermutation.
Types of Mutations
Mutations can be classified in several ways, depending on the nature of the change and its effects on the organism. Some of the most common types include:
- Point mutations: These are changes in a single base pair of a DNA sequence. They can result in different types of amino acids being produced, which can alter the function of the proteins produced by the gene.
- Insertion mutations: These occur when extra base pairs are inserted into a DNA sequence. This can cause a frameshift mutation, which can alter the reading frame of the gene and produce a completely different protein.
- Deletion mutations: These occur when a section of DNA is lost, or deleted. Like insertions, deletions can cause frameshift mutations.
- Duplication mutations: These occur when a section of DNA is duplicated and inserted back into the genome. This can result in the production of extra copies of a gene, which can have various effects on the organism.
- Inversion mutations: These occur when a section of DNA is reversed within the genome. This can disrupt the function of the affected genes, and can also lead to the production of new genes.
Effects of Mutations
The effects of mutations can vary widely, from no noticeable effect to significant changes in an organism's phenotype. Some mutations can be beneficial, giving the organism an advantage in its environment, while others can be harmful or even lethal. Many mutations, however, are neutral, having no effect on the organism's fitness.
Mutations can also lead to genetic variation within a population, which is a key factor in evolution. In fact, all genetic variation in living organisms is ultimately due to mutations.
External links
- Medical encyclopedia article on Mutations
- Wikipedia's article - Mutations
This WikiMD article is a stub. You can help make it a full article.
Languages: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
Urdu,
বাংলা,
తెలుగు,
தமிழ்,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
European
español,
Deutsch,
français,
русский,
português do Brasil,
Italian,
polski