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A nucleotide sequence that is found in a gene, codes information for protein synthesis, and is transcribed to messenger RNA.

[ex(pressed) + -on.]

ex·on′ic adj.


(Historical Terms) Brit one of the four officers who command the Yeomen of the Guard
[C17: a pronunciation spelling of French exempt exempt]


(Genetics) any segment of a discontinuous gene the segments of which are separated by introns. Compare intron
[C20: from ex-1 + -on]
exˈonic adj


(ˈɛk sɒn)

a segment of DNA that is transcribed to RNA and specifies the sequence of a portion of protein.
[1975–80; ex(pressed sequence) + -on1]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.exon - sequence of a gene's DNA that transcribes into protein structures; "exons are interspersed with introns"
deoxyribonucleic acid, desoxyribonucleic acid, DNA - (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information; "DNA is the king of molecules"
intron, noncoding DNA - sequence of a eukaryotic gene's DNA that is not translated into a protein
References in periodicals archive ?
12, 2015 /PRNewswire/ -- Blueprint Medicines (NASDAQ: BPMC) today announced that it will present new preclinical data demonstrating the potential utility of BLU-285 in a subset of patients with acute myeloid leukemia (AML) characterized by a mutation in KIT Exon 17 during an oral presentation at the 2015 American Society of Hematology (ASH) Annual Meeting and Exposition being held December 5-8 in Orlando, Fla.
Finally, we will take advantage of the CRISPR-Cas9 technology to generate exon specific knockouts in mouse embryos in order to assess their role during early embryo development.
In the present study, two SNPs were detected, locating in exon 3 of the Mrf4 gene, and in exon 1 of the MyoD gene.
The 5' proximal end of dystrophin is more susceptible to duplication events and the most common exonic duplication mutation in DMD/ BMD patients has been shown to involve exon 2.
Cloning of this amplicon and reanalysis by Sanger sequencing revealed a 142-bp deletion located in intron 7/8 and exon 8.
0105) for AKT1 exon 2 assay or PIK3CA exon 20 assay, respectively, and distilled water to a final volume of 20 [micro]L.
Although the sample size was small, this report suggests that exon copy number variants of CFTR is not a major mutational mechanism giving rise to CF in black and coloured southern African CF patients.
Four of them were already reported as a polymorphism in another study (11,12), but it was unclear whether a substitution glycine for aspartic acid in exon 26 (D682G) was mutation or polymorphism.
The exon skip occurs during the intermediate phase between the gene and the protein at the moment of splicing (1), and allows production of a truncated but functional protein to be restored.
Exon 3 encoded a hydrophilic domain containing multiple stop codons that would result in truncation of MOG prior to translation of its transmembrane domain.