deletion mutation

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Related to deletion mutation: Insertion mutation, inversion mutation

read·ing-·frame·shift mu·ta·tion

a mutation that results from insertion or deletion of a single nucleotide into, or from, the normal DNA sequence; because the genetic code is read three nucleotides at a time, all nucleotide triplets distal to the mutation will be one step out of phase and misread, and hence translated as different amino acids.

deletion mutation

a type of MUTATION in which genetic material is removed from chromosomes or other DNA molecules (see CHROMOSOMAL MUTATION, POINT MUTATION). The deletion can be as small as a single DNA base (which can cause a misreading of the base sequence during PROTEIN SYNTHESIS, see FRAMESHIFT) to a large tract of DNA containing many GENES.


1. a nucleotide change, including base substitutions, insertions or deletions in DNA, or RNA in the case of some viruses, that gives rise to the mutant phenotype.
2. an animal exhibiting such change. Called also a sport.

back mutation
see reverse mutation (below).
base substitution mutation
may be a transition in which a purine-pyrimidine pair is substituted by the other purine-pyrimidine pair, or transversion in which a purine-pyrimidine pair is replaced by one of the two pyrimidine pairs.
chain termination mutation
one in which the new base sequence introduces a stop codon and thereby prematurely terminates synthesis of the polypeptide; the three mutations are also called amber (UAG), ochre (UAA) and opal (UGA).
deletion mutation
one produced by loss of nucleotides from a DNA sequence.
frame shift mutation
occur as a result of either the insertion of a new base pair or the deletion of a base pair or a block of base pairs from the DNA base sequence; these, unless they occur in 3 or multiples of 3, are most serious in that the message to the right of the frame shift is garbled.
leaky mutation
one in which the amino acid substitution only partially disrupts the function of the protein; in bacteria this is usually manifested by reduced growth rate.
mis-sense mutation
one causing an amino acid substitution in the protein.
nonsense mutation
one in which a stop codon is substituted for a codon that specifies an amino acid.
operator constitutive mutation
one or more base changes in the operator region (originally defined for the lactose operon) which stop the repressor protein from tightly binding to sequence such that it is less effective in preventing RNA polymerase from inhibiting transcription.
point mutation
a single changed base pair in the DNA of an organism which may be a base substitution, base insertion or base deletion.
mutation rate
the frequency of mutations in the population over time.
repressor-constitutive mutation
in regulation of gene expression, a mutation in the repressor protein that decreases the binding affinity of the repressor protein for the operator which leaves the gene permanently turned on.
reverse mutation
one in which the wild-type phenotype is restored; such organisms are called revertants. Called also back mutation, reversion mutation.
second-site mutation
see suppressor mutation.
silent mutation
one in which there is a base change but because of the redundancy of the genetic code the same amino acid is coded, or one in which there is an amino acid substitution in the protein which has no detectable effect on the phenotype.
somatic mutation
a change in the DNA sequence that occurs in somatic cells, i.e. not gametes. The mechanism underlying the generation of diversity of antigen recognition by immunoglobulins and T cell receptor molecules. The fundamental cause of cancer, in which the mutation occurs spontaneously or is induced by carcinogens, such as sunlight, chemicals or viruses.
suppressor mutation
a particular type of reversion mutation in which a mutation at a second site restores the original phenotype; most simply a mutation produced by a base deletion may be restored to wild type by a proximate but independent base substitution. Called also second-site mutation.
temperature-sensitive (ts) mutation
one in which there is an altered protein that is active at one temperature, typically 86°F (30°C) and inactive at a higher temperature, usually 104 to 108°F (40 to 42°C), e.g. ts mutant virus and bacteria.
transdominant mutation
occur in genes producing diffusible products, in contrast to cis-dominant mutation in which mutations occur in regulatory sequences that are recognized by other proteins.
transition mutation
one in which the base change does not change the pyrimidine-purine orientation. See also base substitution mutation (above).
transposition mutation
one produced by the insertion of a transposable genetic element.
transversion mutation
one in which the purine-pyrimidine orientation is changed to pyrimidine-purine or vice versa. See also base substitution mutation (above).
References in periodicals archive ?
It was also necessary to detect deletion mutations within a large amount of wild-type DNA because random mutations occur at a low frequency in the gene of interest.
The deletion mutation of porcine TIAF1 gene, which was found in its exon, causes deletion of two amino acids, which might alter the protein structure and lead to functional variation such as the interaction with TGF[beta]1.
These viruses have a characteristic deletion mutation in the HA molecule at residue 134.
Mutations in the spectrin beta nonerythrocytic 2 gene ( SPTBN2 ) are known to cause SCA5, six of which have been reported, including three missense mutations and three deletion mutations.
Thus, duplication mutations in affected boys, and duplication or deletion mutations in heterozygous females cannot be identified using this technique.
As shown in Table S2 in the online Data Supplement, all point mutations and all deletion mutations were found to be stable.
In particular, resistance to rifampin is associated with missense, insertion, and deletion mutations in the rifampin resistance-determining region (RRDR) of rpoB, which encodes the [beta] subunit of the DNA-dependent RNA polymerase (17,18).
3-kb PCR product covering the entire coding region and found a 2-bp deletion mutation at nucleotides 11 008-11 009.
We screened 45 unrelated FH heterozygotes using this scheme and identified two large deletion mutations in four FH families: one is a novel 2-kb deletion including exon 7, and the other is a 5.
The deletion mutation occurred in the sequence consisting of two direct repeats; only one copy of the repeat was retained in the mutant gene.
This targeted assay consists of 2 parts, one for each of the 2 most common EGFR mutations: a TaqMan (Applied Biosystems, Foster City, California) "real-time" PCR assay for the L858R point mutation in exon 21, and a capillary electrophoresis sizing assay to screen for deletion mutations in exon 19.