: a variant DNA sequence in which the purine or pyrimidine base (such as cytosine) of a single nucleotide has been replaced by another such base (such as thymine)

Word History

Etymology

single nucleotide polymorphism

First Known Use

1991, in the meaning defined above

Time Traveler
The first known use of SNP was in 1991

Dictionary Entries Near SNP

Cite this Entry

“SNP.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/SNP. Accessed 21 Feb. 2024.

Medical Definition

SNP

noun
: a variant DNA sequence in which the purine or pyrimidine base (as cytosine) of a single nucleotide has been replaced by another such base (as thymine)
Most SNPs occur in places in the genome that aren't used for making proteins—the so-called junk DNA. But the few SNPs that land squarely in a gene or in a regulatory region near a gene can alter characteristics influenced by that gene …Christen Brownlee, Science News
The ultimate goal of the pharmaceutical industry is to find the SNPs involved with major diseases and use them to find specific molecular targets for drugs.Tim Friend, USA Today

called also single nucleotide polymorphism

More from Merriam-Webster on SNP

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