Mutation

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mutation

 [mu-ta´shun]
1. a permanent transmissible change in the genetic material.
2. an individual exhibiting such a change.
point mutation a mutation resulting from a change in a single base pair in the DNA molecule.
somatic mutation a genetic mutation occurring in a somatic cell, providing the basis for mosaicism.
suppressor mutation the correction of the effect of a mutation at one locus by a mutation at another locus.

mu·ta·tion

(myū-tā'shŭn),
1. A change in the chemistry of a gene that is perpetuated in subsequent divisions of the cell in which it occurs; a change in the sequence of base pairs in the chromosomal molecule.
2. De Vries, term for the sudden production of a species, as distinguished from variation.
[L. muto, pp. -atus, to change]

mutation

(myo͞o-tā′shən)
n.
1. The act or process of being altered or changed.
2. An alteration or change, as in nature, form, or quality.
3. Genetics
a. A change in the nucleotide sequence of the genome of an organism or virus, sometimes resulting in the appearance of a new character or trait not found in the parental type.
b. The process by which such a change occurs, either through an alteration in the nucleotide sequence coding for a gene or through a change in the physical arrangement of the genetic material.
c. The nucleotide sequence, trait, or individual that results from such a change.

mu·ta′tion·al adj.
mu·ta′tion·al·ly adv.

mutation

(1) The process by which genes undergo a permanent and heritable change in nucleotide sequence that differs from either parental haploid contribution to the progeny.
(2) A heritable change in a DNA sequence.

Mutations either occur spontaneously or result from environmental exposure to mutagenic agents (e.g., chemicals, radiation). Most mutations either have no effect, are deleterious, or are lethal; some provide survival benefits, which are passed on to progeny. 

Examples
Deletions, duplications, extranuclear changes, insertions, point mutations, rearrangements, tandem repeat amplifications, translocations.

mu·ta·tion

(myū-tā'shŭn)
1. A change in the chemistry of a gene that is perpetuated in subsequent divisions of the cell in which it occurs; a change in the sequence of base pairs in the chromosomal molecule.
2. The sudden production of a species, as distinguished from variation.
[L. muto, pp. -atus, to change]

mutation

Any persisting change in the genetic material (DNA) of a cell. Mutations most commonly involve a single gene but may affect a major part, or even the whole of, a chromosome or may change the number of chromosomes (genomic mutation). A nonsense mutation is one that alters the sequence of bases in a CODON so that no amino acid is coded. Many mutations have an unfavourable effect on the cell concerned and are not passed on, but non-lethal mutations are replicated in daughter cells. Mutation in a cell in the GONADS that gives rise to a SPERMATOZOON or an egg (OVUM), will be passed on to a clone of sperms or eggs and one of these may take part in fertilization so that the mutation is passed on to every cell in the body of the future individual, including the GERM CELLS. New mutations occurring in the sex cells (germ line mutations) may thus lead to hereditary abnormalities. Mutations in body cells (somatic mutations) cannot do this but can cause cloned abnormalities including cancers. See also FRAME SHIFT MUTATION, INSERTION MUTATION, INVERSION MUTATION, LEAKY MUTATION, LETHAL MUTATION, MISSENSE MUTATION, POINT MUTATION, NONSENSE MUTATION.

mutation

a change in the genetic material of an organism. In eukaryotes, if the alteration affects gametic cells the change is a genetic mutation and can be inherited; if body cells (nonsexual) are affected the mutation is called somatic mutation and will not normally be inherited. Mutations that result in alterations to a gene produce a different ALLELE. Mutation can also affect the number of chromosomes. See also SPONTANEOUS MUTATION, INDUCED MUTATION, CHROMOSOMAL MUTATION.

Mutation

A permanent change in the genetic material that may alter a trait or characteristic of an individual, or manifest as disease, and can be transmitted to offspring.

mutation

A permanent transmissible change in the nucleotide sequence of the DNA within a gene, or a change in the physical structure of a chromosome. It can occur by substitution (one base or nucleotide is replaced by another), transition (a purine (adenine or guanine) is replaced by another purine or one pyrimidine (cytosine or thymine) is replaced by another pyrimidine), transversion (a pyrimidine is replaced by a purine or vice versa), deletion or insertion of one or more bases. Mutations can also occur in a chromosome as a result of inversion (a segment of chromosome is inserted in reverse order), deletion (a loss of a piece of chromosome) or translocation (a piece of chromosome attaches to another). Mutations result in the formation of a protein with an abnormal amino acid or an absence of the protein and these may result in disease but some mutations may be beneficial. Mutations may be caused by copying errors in the genetic material during cell division, by exposure to ultraviolet or ionizing radiation (X-rays, gamma rays), carcinogens, viruses, or spontaneously. See chromosome; gene.

mu·ta·tion

(myū-tā'shŭn)
Change in gene chemistry perpetuated in subsequent divisions of cell in which it occurs.
[L. muto, pp. -atus, to change]
References in periodicals archive ?
They investigated a total of 419 animals and detected five carriers with 1.2% frequency of mutant alleles. Since then, various studies on incidence of FXI deficiency in dairy cattle breeds such as Holstein, Friesian and their cross-breds have been reported from different countries.
The following SNP mutant alleles significantly increase the risk of spontaneous abortion: TLR9 A (OR = 7.03, p < 0.0001) (Table 5), IL-10 A (OR = 2.85, p = 0.0003) (Table 15), TLR2 A (OR = 5.76, p = 0.06) (Table 2), and TLR4 T(OR = 2.49, p = 0.07) (Table 3).
Zernant-Rajang et al., "G1961E mutant allele in the Stargardt disease gene ABCA4 causes bull's eye maculopathy," Experimental Eye Research, vol.
We successfully amplified all 351 samples for pfcrt and sequenced the amplification products; mutant alleles were found at codons M74I, N75E, and K76T only in 8 (2.3%) samples.
In UC patients, the mutant alleles and genotypes of FUT2 (C357T, A385T, and G428A) did not statistically differ between patients with extensive colitis and distal colitis.
The mutant allele C was more frequent among ACS ST (+) than ACS ST (-) patients, when the wild-type allele was more represented in the ACS ST (-) group.
It was concluded that FMO3 mutant allele coding proteins with impaired activity ultimately resulted in changes of the clinical consequence for FMO3 substrates.
(a) RS2_W where [TGG] is wild-type allele with normal raffinose and [*3 bp] is mutant allele with reduced raffinose; (b) RS2_397 where [CC] is wild-type allele with normal raffinose and [TT] is mutant allele with reduced raffinose; (c) Lox-1 where [*] is wild-type with normal lipoxygenase and [*74] is mutant allele with reduced lipoxygenase; (d) Lox-2 where [TT] is wild-type allele and [AA] is mutant allele with reduced lipoxygenase; (e) Lox3_G_100 where [GG] is wild-type allele and [*] is mutant allele with reduced lipoxygenase.
The percentage of patients with stage IV cancer carrying the mutant allele was higher than among the normal homozygotes (32.9% v.
Mutations in VKORC1, which is responsible for activation of vitamin K-dependent clotting factors, decrease the conversion of vitamin K-epoxide to vitamin K; therefore, lower doses are required in individuals carrying the mutant allele. (14) Because of this information, current US Food and Drug Administration (FDA)-approved drug labeling for warfarin includes 3 ranges of expected maintenance doses (Supplemental Table 1) (see supplemental material file at www.
The highest allele frequencies are observed among North European populations--for example in Denmark being 12.9% (n=105), Sweden 12.7% (n=1057) and Great Britain 12.3% (n=367), but also a high prevalence of the mutant allele was observed in Slovakia 14.4% (n =335) [4,6,19-21,29, 30].
The gene is located on chromosome 3 and has a mutant allele with a 32 bp deletion known as CCR5[DELTA]32, which leads to truncation and loss of the receptor on the cell surface [13, 14].