Mutation

mutationsgenetic mutationmutatedgenetic mutationssomatic mutationmutatede novogene mutationloss-of-functionloss of function
In biology, a mutation is the alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA.wikipedia
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Evolution

evolvedtheory of evolutionevolutionary
Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity.
Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources of genetic variation.

Mitosis

mitoticmitosesmitotic division
Mutations result from errors during DNA replication, mitosis, and meiosis, or other types of damage to DNA (such as pyrimidine dimers that may be caused by exposure to radiation or carcinogens), which then may undergo error-prone repair (especially microhomology-mediated end joining ), or cause an error during other forms of repair, or else may cause an error during replication (translesion synthesis).
Other errors during mitosis can induce apoptosis (programmed cell death) or cause mutations.

Deletion (genetics)

deletiondeletionsmicrodeletion
Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements.
In genetics, a deletion (also called gene deletion, deficiency, or deletion mutation) (sign: Δ) is a mutation (a genetic aberration) in which a part of a chromosome or a sequence of DNA is left out during DNA replication.

Genetic variation

variationinterindividual variabilitygenetic variations
One study on genetic variations between different species of Drosophila suggests that, if a mutation changes a protein produced by a gene, the result is likely to be harmful, with an estimated 70 percent of amino acid polymorphisms that have damaging effects, and the remainder being either neutral or marginally beneficial.
There are multiple sources of genetic variation, including mutation and genetic recombination.

Gene

genesnumber of genesgene sequence
Mutations in genes can either have no effect, alter the product of a gene, or prevent the gene from functioning properly or completely.
Genes can acquire mutations in their sequence, leading to different variants, known as alleles, in the population.

Polymorphism (biology)

polymorphismpolymorphicmorph
One study on genetic variations between different species of Drosophila suggests that, if a mutation changes a protein produced by a gene, the result is likely to be harmful, with an estimated 70 percent of amino acid polymorphisms that have damaging effects, and the remainder being either neutral or marginally beneficial.
Genetic polymorphism is a term used somewhat differently by geneticists and molecular biologists to describe certain mutations in the genotype, such as single nucleotide polymorphisms that may not always correspond to a phenotype, but always corresponds to a branch in the genetic tree.

RNA virus

RNA virusesRNARNA genome
The genomes of RNA viruses are based on RNA rather than DNA.
RNA viruses generally have very high mutation rates compared to DNA viruses, because viral RNA polymerases lack the proofreading ability of DNA polymerases.

Transposable element

transposontransposable elementstransposons
Sequences of DNA that can move about the genome, such as transposons, make up a major fraction of the genetic material of plants and animals, and may have been important in the evolution of genomes.
A transposable element (TE, transposon, or jumping gene) is a DNA sequence that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size.

Natural selection

selectionselectiveselected
The abundance of some genetic changes within the gene pool can be reduced by natural selection, while other "more favorable" mutations may accumulate and result in adaptive changes.
This occurs partly because random mutations arise in the genome of an individual organism, and offspring can inherit such mutations.

Species

specificspecific epithetspecific name
One study on genetic variations between different species of Drosophila suggests that, if a mutation changes a protein produced by a gene, the result is likely to be harmful, with an estimated 70 percent of amino acid polymorphisms that have damaging effects, and the remainder being either neutral or marginally beneficial.
Genetic variability arises from mutations and recombination, while organisms themselves are mobile, leading to geographical isolation and genetic drift with varying selection pressures.

Neutral mutation

neutralconservativenear-neutral
Neutral mutations are defined as mutations whose effects do not influence the fitness of an individual.
In population genetics, mutations in which natural selection does not affect the spread of the mutation in a species are termed neutral mutations.

HIV

human immunodeficiency virusHIV-positiveHIV positive
In some of these viruses (such as the single-stranded human immunodeficiency virus) replication occurs quickly and there are no mechanisms to check the genome for accuracy.
These advances in structural biology were made possible due to the development of stable recombinant forms of the viral spike by the introduction of an intersubunit disulphide bond and an isoleucine to proline mutation (radical replacement of an amino acid) in gp41.

Saltation (biology)

saltationismsaltationsaltational
Before Darwin, biologists commonly believed in saltationism, the possibility of large evolutionary jumps, including immediate speciation.
In biology, saltation (from Latin, saltus, "leap") is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation.

Gene duplication

duplicationduplicationsamplification
Mutations can involve the duplication of large sections of DNA, usually through genetic recombination.
Duplication creates genetic redundancy, where the second copy of the gene is often free from selective pressure—that is, mutations of it have no deleterious effects to its host organism.

Virus

virusesviralvirion
In biology, a mutation is the alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA.
These include a process called antigenic drift where individual bases in the DNA or RNA mutate to other bases.

Speciation

divergedspeciatedspeciate
Before Darwin, biologists commonly believed in saltationism, the possibility of large evolutionary jumps, including immediate speciation. In evolution, the most important role of such chromosomal rearrangements may be to accelerate the divergence of a population into new species by making populations less likely to interbreed, thereby preserving genetic differences between these populations.
In most instances, they indicate a (non-silent) mutation, which is almost certain to be deleterious.

DNA damage (naturally occurring)

DNA damageDNA damagesdamage
Four classes of mutations are (1) spontaneous mutations (molecular decay), (2) mutations due to error-prone replication bypass of naturally occurring DNA damage (also called error-prone translesion synthesis), (3) errors introduced during DNA repair, and (4) induced mutations caused by mutagens.
DNA damage is distinctly different from mutation, although both are types of error in DNA.

Genetic drift

driftrandom genetic driftrandom drift
These can increase in frequency over time due to genetic drift.
In 1968, population geneticist Motoo Kimura rekindled the debate with his neutral theory of molecular evolution, which claims that most instances where a genetic change spreads across a population (although not necessarily changes in phenotypes) are caused by genetic drift acting on neutral mutations.

Hugo de Vries

de VriesDe Vries, Hugo MarieHugo DeVries
In 1901 the geneticist Hugo de Vries gave the name "mutation" to seemingly new forms that suddenly arose in his experiments on the evening primrose Oenothera lamarckiana, and in the first decade of the 20th century, mutationism, or as de Vries named it mutationstheorie, became a rival to Darwinism supported for a while by geneticists including William Bateson, Thomas Hunt Morgan, and Reginald Punnett.
He is known chiefly for suggesting the concept of genes, rediscovering the laws of heredity in the 1890s while apparently unaware of Gregor Mendel's work, for introducing the term "mutation", and for developing a mutation theory of evolution.

Mutagen

mutagenicmutagenicitymutagens
Four classes of mutations are (1) spontaneous mutations (molecular decay), (2) mutations due to error-prone replication bypass of naturally occurring DNA damage (also called error-prone translesion synthesis), (3) errors introduced during DNA repair, and (4) induced mutations caused by mutagens.
In genetics, a mutagen is a physical or chemical agent that changes the genetic material, usually DNA, of an organism and thus increases the frequency of mutations above the natural background level.

DNA

deoxyribonucleic aciddouble-stranded DNAdsDNA
Mutations result from errors during DNA replication, mitosis, and meiosis, or other types of damage to DNA (such as pyrimidine dimers that may be caused by exposure to radiation or carcinogens), which then may undergo error-prone repair (especially microhomology-mediated end joining ), or cause an error during other forms of repair, or else may cause an error during replication (translesion synthesis).
Despite the importance of 5-methylcytosine, it can deaminate to leave a thymine base, so methylated cytosines are particularly prone to mutations.

Cancer

cancersmalignanciescancerous
Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity.
More common are mutations, which are changes in the nucleotide sequence of genomic DNA.

Mutant

mutantsmutatedsport
Scientists may also deliberately introduce mutant sequences through DNA manipulation for the sake of scientific experimentation.
In biology and especially genetics, a mutant is an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism.

Human

humanshuman beinghuman beings
For example, the human eye uses four genes to make structures that sense light: three for cone cell or color vision and one for rod cell or night vision; all four arose from a single ancestral gene.
Found by scanning through genomic databases of multiple species, some of these highly mutated areas may contribute to human-specific traits.

DNA repair

DNA damagerepairtranslesion synthesis
Mutations result from errors during DNA replication, mitosis, and meiosis, or other types of damage to DNA (such as pyrimidine dimers that may be caused by exposure to radiation or carcinogens), which then may undergo error-prone repair (especially microhomology-mediated end joining ), or cause an error during other forms of repair, or else may cause an error during replication (translesion synthesis).
Other lesions induce potentially harmful mutations in the cell's genome, which affect the survival of its daughter cells after it undergoes mitosis.