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Point mutation

Definition(s)

An alteration in DNA sequence caused by a single nucleotide base change, insertion, or deletion.

Definition from: GeneReviewsThis link leads to a site outside Genetics Home Reference. from the University of Washington and the National Center for Biotechnology Information

A gene mutation involving the substitution, addition, or deletion of a single nucleotide base.

Definition from: Merriam-Webster's Medical DictionaryThis link leads to a site outside Genetics Home Reference. by Merriam-Webster Inc.

A point mutation is when a single base pair is altered. Point mutations can have one of three effects. First, the base substitution can be a silent mutation where the altered codon corresponds to the same amino acid. Second, the base substitution can be a missense mutation where the altered codon corresponds to a different amino acid. Or third, the base substitution can be a nonsense mutation where the altered codon corresponds to a stop signal.

Definition from: Talking Glossary of Genetic TermsThis link leads to a site outside Genetics Home Reference. from the National Human Genome Research Institute

Related discussion in the Handbook

See also Understanding Medical Terminology.

 
Published: May 25, 2015