point mutation


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Related to point mutation: Insertion mutation, Deletion mutation

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.

point mu·ta·tion

a mutation that involves a single nucleotide; it may consist of loss of a nucleotide, substitution of one nucleotide for another, or the insertion of an additional nucleotide.

point mutation

n.
A mutation that changes one nucleotide in a gene or DNA sequence by substitution, deletion, or addition.

point mu·ta·tion

(poynt myū-tā'shŭn)
A mutation that involves a single nucleotide; it may consist of loss of a nucleotide, substitution of one nucleotide for another, or the insertion of an additional nucleotide.

point mutation

The replacement of one NUCLEOTIDE with another. This need not necessarily cause any change in the protein produced by the affected gene because 18 of the 20 amino acids have more than one coding triplet of base pairs (codon). Glycine, for instance, is coded for by GGA, GGU, GGG and GGC. This redundancy feature of the genetic code arises because the four bases, taken three at a time, allow 64 triplets to code the 20 amino acids and the three stop codons. It is called degeneracy.

point mutation

or

gene mutation

a genetic change affecting a single LOCUS, producing an alternative ALLELE of the gene, but not a gross structural change to the chromosome. The genetic change consists of an altered sequence of DNA bases, which can be of three main types:
  1. (a) a SUBSTITUTION MUTATION,
  2. (b) a DELETION MUTATION and
  3. (c) an INSERTION MUTATION, the latter two often causing a major change to the amino acid sequence of the protein structure. Compare CHROMOSOMAL MUTATION.
References in periodicals archive ?
A novel complex allele and two new point mutations in type 2 (acute neuronopathic) Gaucher disease.
Importantly, in studies of point mutations, the targets are typically longer than the probes.
Another extremely sensitive technique for detection of specific point mutations is A50-PCR.
Rapid detection of six common Mediterranean and three non-Mediterranean [alpha]-thalassemia point mutations by reverse dot blot analysis.
This finding indicates that the point mutation of the amelogenin gene may alter the localization or increase the protein expression of Grp78.
Other mutations in the Jak2 gene such as exon 13 and 15 also exhibits the same disease symptoms.4,12 Mutation in Jak2 gene showed frame shift, missense and point mutations. Jak2 exon 14 has H606Q, H608Y, V617I, and C618R.
A study by Robinson found that cancer development is micro-evolutionary process, in which merely a single point mutation is not responsible for cancer outbreak, but single mutation can start the process of chaos in the genome.
Combining the detection of point mutations with copy number variation (CNV) can result in significant time savings in laboratories.
(7) reported a truncating de novo point mutation in a patient with severe MD who presented with hypotonia, epilepsy, and dysmorphic facial features.
That's useful because sometimes just one base pair in a long strand of DNA gets swapped, deleted, or inserted--a phenomenon called a point mutation. Point mutations make up 32,000 of the 50,000 changes in the human genome known to be associated with diseases.
Compound heterozygous (2-5%) individuals possess a GAA trinucleotide repeat expansion on one allele and a point mutation on the other allele.
It has been found that the most likely cause for the resistance to imatinib found in a proportion of patients can be linked to point mutation in the BCR-ABL kinase domain.