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Polymorphism

Synonym(s)

  • polymorphic allele

Definition(s)

Natural variations in a gene, DNA sequence, or chromosome that have no adverse effects on the individual and occur with fairly high frequency in the general population

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

Polymorphism involves one of two or more variants of a particular DNA sequence. The most common type of polymorphism involves variation at a single base pair. Polymorphisms can also be much larger in size and involve long stretches of DNA. Called a single nucleotide polymorphism, or SNP (pronounced "snip"), scientists are studying how SNPs in the human genome correlate with disease, drug response, and other phenotypes.

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: December 16, 2014