DNA methylation
noun
: 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
John CloudA 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
Helen PilcherA process called DNA methylation sets down "marks" on bits of DNA and is typically thought to squelch gene expression.—Sarah Baldauf
Sarah BaldaufDNA methylation is a mark on genomic DNA made by addition of methyl groups to cytosine bases …—Adrian Bird
Adrian BirdExamples of DNA methylation in a Sentence
Recent Examples on the Web
As for how this might happen, Choi pointed to higher temperatures potentially triggering cellular stress and inflammation, as well as influencing DNA methylation patterns.
—Brian Mastroianni, Health, 10 Mar. 2025
Research in animal models has shown that extreme heat can trigger what’s known as a maladaptive epigenetic memory, or lasting changes in DNA methylation patterns.
—Eunyoung Choi, The Conversation, 4 Mar. 2025
Other tools, such as the Epigenetic Clock, which measures DNA methylation patterns, provide complementary information about biological age.
—William A. Haseltine, Forbes, 26 Feb. 2025
In 2011, geneticist Steve Horvath, along with a team of researchers at UCLA, homed in on a system that could accurately estimate a person’s biological age based on several DNA methylation markers in the blood.
—New Atlas, 2 Feb. 2025
The study also measured changes in the participants’ DNA methylation — a method used by cells to control gene expression — which are strongly correlated with aging.
—Aria Bendix, NBC News, 1 Jan. 2025
One way to assess biological age is by focusing on a biological process known as DNA methylation, which involves molecular changes over time that turn different genes on and off.
—Lisa Rapaport, EverydayHealth.com, 29 July 2024
The key biomarker was change in DNA methylation – the process by which a small molecule known as a methyl group is added to DNA or proteins, essentially inhibiting or triggering gene expression.
—New Atlas, 28 July 2024
Between the two groups of animals, consistent variations in DNA methylation–a process where methyl groups bind to regions of the genome within a cell, and silence certain genes–are detectable.
—Lauren Leffer, Popular Science, 28 Mar. 2024
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Brian Mastroianni, Health, 10 Mar. 2025
Research in animal models has shown that extreme heat can trigger what’s known as a maladaptive epigenetic memory, or lasting changes in DNA methylation patterns.
—Eunyoung Choi, The Conversation, 4 Mar. 2025
Other tools, such as the Epigenetic Clock, which measures DNA methylation patterns, provide complementary information about biological age.
—William A. Haseltine, Forbes, 26 Feb. 2025
In 2011, geneticist Steve Horvath, along with a team of researchers at UCLA, homed in on a system that could accurately estimate a person’s biological age based on several DNA methylation markers in the blood.
—New Atlas, 2 Feb. 2025
The study also measured changes in the participants’ DNA methylation — a method used by cells to control gene expression — which are strongly correlated with aging.
—Aria Bendix, NBC News, 1 Jan. 2025
One way to assess biological age is by focusing on a biological process known as DNA methylation, which involves molecular changes over time that turn different genes on and off.
—Lisa Rapaport, EverydayHealth.com, 29 July 2024
The key biomarker was change in DNA methylation – the process by which a small molecule known as a methyl group is added to DNA or proteins, essentially inhibiting or triggering gene expression.
—New Atlas, 28 July 2024
Between the two groups of animals, consistent variations in DNA methylation–a process where methyl groups bind to regions of the genome within a cell, and silence certain genes–are detectable.
—Lauren Leffer, Popular Science, 28 Mar. 2024
Cite this Entry
“DNA methylation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/DNA%20methylation. Accessed 25 Mar. 2025.
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