DNA methylation


Definition of DNA methylation

: the enzymatically controlled addition of a methyl group to a nucleotide base (such as cytosine in eukaryotes) in a molecule of DNA that plays a role in regulating gene expression (as by the inhibition of genetic transcription) When a methyl group attaches to a specific spot on a gene—a process called DNA methylation—it can change the gene's expression, turning it off or on, dampening it or making it louder.— John Cloud A handful of drugs that affect DNA methylation already exist, and are being used to treat cancers in which faulty gene labeling plays a role.— Helen Pilcher A process called DNA methylation sets down "marks" on bits of DNA and is typically thought to squelch gene expression.— Sarah Baldauf DNA methylation is a mark on genomic DNA made by addition of methyl groups to cytosine bases …— Adrian Bird

First Known Use of DNA methylation

1963, in the meaning defined above

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The first known use of DNA methylation was in 1963

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Cite this Entry

“DNA methylation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/DNA%20methylation. Accessed 28 Oct. 2020.

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DNA methylation


Medical Definition of DNA methylation

: the enzymatically controlled methylation of a nucleotide base (as cytosine in eukaryotes) in a molecule of DNA that plays a role in suppressing gene expression

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