single nucleotide polymorphism
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the ability to exist in several different forms.
balanced polymorphism an equilibrium mixture of homozygotes and heterozygotes maintained by natural selection against both homozygotes.
genetic polymorphism the occurrence together in the same population of two or more genetically determined phenotypes in such proportions that the rarest of them cannot be maintained merely by recurrent mutation.
single nucleotide polymorphism (SNP) a genetic polymorphism between two genomes that is based on deletion, insertion, or exchange of a single nucleotide.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
single nucleotide polymorphism (SNP),
the naturally occurring substitution of a single nucleotide at a given location in the genome of an organism, the more interesting of which results in phenotypic variability, including alterations in the organism's physiologic responses to endogenous hormones and neurotransmitters or endogenous substances.
Farlex Partner Medical Dictionary © Farlex 2012
single nucleotide polymorphism (SNP, ‘snip’)a single BASE PAIR position in genomic DNA where different sequence alternatives exist for normal individuals in the population. Differences between individual genomes are largely due to SNPs. Over 1.4 million SNPs have been identified in the human GENOME. SNPs in coding regions of the genome are designated cSNPs; those in regulatory regions, rSNPs; and those in JUNK DNA regions, anonymous SNPs. SNPs generate variability, particularly where they occur in coding regions, thereby contributing to the biological characteristics of an individual. For example SNPs reflect differences in susceptibility to, and protection from, a range of diseases. An SNP can be detected by OLIGONUCLEOTIDE HYBRIDIZATION, using for example DNA CHIPS.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005