intron

American  

[in-tron] / ˈɪn trɒn /

noun

Genetics.

1. a noncoding segment in a length of DNA that interrupts a gene-coding sequence or nontranslated sequence, the corresponding segment being removed from the RNA copy before transcription.

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intron British  

/ ˈɪntrɒn /

noun

1. biochem a stretch of DNA that interrupts a gene and does not contribute to the specification of a protein Compare exon 2

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intron Scientific  

/ ĭn′trŏn /

1. A segment of a gene situated between exons that does not function in coding for protein synthesis. After transcription of a gene to messenger RNA, the transcriptions of introns are removed, and the exons are spliced together by enzymes before translation and assembly of amino acids into proteins.

2. Compare exon

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intron Cultural  

1. A stretch of DNA in a gene that does not code for proteins. In eukaryotes, introns in a given gene separate stretches of DNA that contain instructions for constructing proteins. (Compare exon.)

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Etymology

Origin of intron

1975–80; perhaps intr(o)- + -on ¹

Example Sentences

This discovery provides the strongest indication we have so far that spliceosomes could be able to reinsert an intron back into the genome in another location.

From Science Daily • May 10, 2024

Only finished mRNAs that have undergone 5' capping, 3' polyadenylation, and intron splicing are exported from the nucleus to the cytoplasm.

From Textbooks • Jun. 9, 2022

An even more sprawling gene—dystrophin, the Jacksonville of human DNA—contains 14,000 bases of coding DNA spread among 2.2 million bases of intron cruft.

From Slate • Jul. 12, 2012

A mutation that jettisons a base in an intron can have dire consequences: inserting intron sequences into the protein, or obliterating the careful stitching together of exons, dropping gene sections.

From Scientific American • May 16, 2012

Cufflinks was run with default settings, with a maximum intron length of 15,000.

From Nature • Jul. 13, 2011