polymorphism
noun
poly·mor·phism
ˌpä-lē-ˈmȯr-ˌfi-zəm 
: the quality or state of existing in or assuming different forms: such as
a(1)
: existence of a species in several forms independent of the variations of sex
(2)
: existence of a gene in several allelic forms
also
: a variation in a specific DNA sequence
(3)
: existence of a molecule (such as an enzyme) in several forms in a single species
b
: the property of crystallizing in two or more forms with distinct structure
Examples of polymorphism in a Sentence
Recent Examples on the Web
The majority of genetic tests available online look only at a select number of common genetic variables called single nucleotide polymorphisms (SNPs), along with some other markers of genetic variation.
—
WIRED, 21 Sep. 2023
Furthermore, recent studies reveal that the variation between any two individuals is very small, on the order of one single nucleotide polymorphism (SNP), or single letter change in our DNA, per 1,000.
—Alan Goodman, Discover Magazine, 25 June 2020
Today, 'candidate gene' studies focusing on a single polymorphism, of which Blum et al.
—Neuroskeptic, Discover Magazine, 5 July 2015
The trove of primate genomes allowed Farh, Rogers, Marques-Bonet, and colleagues to go hunting for single nucleotide polymorphisms (SNPs), individual DNA base variations within or between species that may change the proteins encoded by genes or alter a gene’s activity.
—Byelizabeth Pennisi, science.org, 1 June 2023
The researchers examined whether there was a relation between the OXTR polymorphisms and the way the dogs interacted with people during the social tests.
—Julie Hecht, Scientific American, 1 May 2017
In contrast, balanced polymorphism frequencies point to a shrinking population or balancing selection. Citation: Casals F, Hodgkinson A, Hussin J, Idaghdour Y, Bruat V, et al.
—Razib Khan, Discover Magazine, 30 Sep. 2013
My proposals on mutation strategies...—see also Amos...—lead to rather precise insights on compensatory mutations or polymorphism propagation, yet they are largely ignored by population geneticists.
—Razib Khan, Discover Magazine, 20 Sep. 2010
Considering the potential functional significance as well as the population differentiation of SNPs located in that region, rs17822931 is the most plausible candidate polymorphism to have undergone geographically restricted positive selection.
—Razib Khan, Discover Magazine, 25 Oct. 2010
See More
WIRED, 21 Sep. 2023
Furthermore, recent studies reveal that the variation between any two individuals is very small, on the order of one single nucleotide polymorphism (SNP), or single letter change in our DNA, per 1,000.
—Alan Goodman, Discover Magazine, 25 June 2020
Today, 'candidate gene' studies focusing on a single polymorphism, of which Blum et al.
—Neuroskeptic, Discover Magazine, 5 July 2015
The trove of primate genomes allowed Farh, Rogers, Marques-Bonet, and colleagues to go hunting for single nucleotide polymorphisms (SNPs), individual DNA base variations within or between species that may change the proteins encoded by genes or alter a gene’s activity.
—Byelizabeth Pennisi, science.org, 1 June 2023
The researchers examined whether there was a relation between the OXTR polymorphisms and the way the dogs interacted with people during the social tests.
—Julie Hecht, Scientific American, 1 May 2017
In contrast, balanced polymorphism frequencies point to a shrinking population or balancing selection. Citation: Casals F, Hodgkinson A, Hussin J, Idaghdour Y, Bruat V, et al.
—Razib Khan, Discover Magazine, 30 Sep. 2013
My proposals on mutation strategies...—see also Amos...—lead to rather precise insights on compensatory mutations or polymorphism propagation, yet they are largely ignored by population geneticists.
—Razib Khan, Discover Magazine, 20 Sep. 2010
Considering the potential functional significance as well as the population differentiation of SNPs located in that region, rs17822931 is the most plausible candidate polymorphism to have undergone geographically restricted positive selection.
—Razib Khan, Discover Magazine, 25 Oct. 2010
See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'polymorphism.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
First Known Use
1839, in the meaning defined above
Phrases Containing polymorphism
Dictionary Entries Near polymorphism
Cite this Entry
“Polymorphism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polymorphism. Accessed 29 Nov. 2023.
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Medical Definition
polymorphism
noun
poly·mor·phism
ˌpäl-i-ˈmȯr-ˌfiz-əm
: the quality or state of existing in or assuming different forms: as
a(1)
: existence of a species in several forms independent of the variations of sex
(2)
: existence of a gene in several allelic forms
also
: a variation in a specific sequence of DNA
(3)
: existence of a molecule (as an enzyme) in several forms in a single species
b
: the property of crystallizing in two or more forms with distinct structure
More from Merriam-Webster on polymorphism
Britannica.com: Encyclopedia article about polymorphism
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