exon

noun

ex·​on ˈek-ˌsän How to pronounce exon (audio)
: a polynucleotide sequence in a nucleic acid that codes information for protein synthesis and that is copied and spliced together with other such sequences to form messenger RNA compare intron
exonic adjective

Examples of exon in a Sentence

Recent Examples on the Web This variant is located within an exon on a gene, GIP, which produces peptides critical in the regulation of various metabolic pathways, in particular insulin response. Razib Khan, Discover Magazine, 7 Dec. 2010 Exondys 51 is used to treat the 13 percent of patients with disease caused by an error in the DNA sequence known as exon 51. BostonGlobe.com, 14 Dec. 2019 Exondys 51 is used to treat the 13% of patients with disease caused by an error in the DNA sequence known as exon 51. Damian Garde, STAT, 12 Dec. 2019 Can the prime editor target a large deletion (adding back as many as five exons) and if so, can it be done that early in the sequence? Sharon Begley, STAT, 6 Nov. 2019 In one case, at Stanford, a toddler was diagnosed with two rare diseases, including a connective tissue disorder called Marfan Syndrome, after doctors conducted a form of sequencing that looks for changes in coded genetic segments known as exons. Anna Gorman, CNN, 8 May 2017 Named for parts of genes called introns and exons, Intrexon was founded in 1998 by Thomas D. Reed and his wife, Jackie, to supply DNA constructs for research with genetically engineered mice. Andrew Pollack, New York Times, 5 Mar. 2016 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'exon.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

expressed sequence + -on entry 2

First Known Use

circa 1978, in the meaning defined above

Time Traveler
The first known use of exon was circa 1978

Dictionary Entries Near exon

Cite this Entry

“Exon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/exon. Accessed 25 Feb. 2024.

Medical Definition

exon

noun
ex·​on ˈek-ˌsän How to pronounce exon (audio)
: a polynucleotide sequence in a nucleic acid that codes information for protein synthesis and that is copied and spliced together with other such sequences to form messenger RNA compare intron
exonic adjective

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