What does methylation mean?
Methylation is the chemical process of attaching a methyl group to a molecule. In molecular biology, methylation most commonly refers to the addition of a methyl group to DNA, although it also occurs in RNA and proteins. DNA methylation can help regulate gene activity, including switching genes on or off without changing the underlying DNA sequence. Alterations in methylation patterns are studied in genetics, cancer research, development, and other fields. More broadly, the term describes any chemical reaction in which a methyl group is introduced into a compound. Because methylation can have important effects on how genetic information is expressed, changes in methylation are a major focus of biological and medical research.
nounThe chemical process of adding a methyl group to a molecule. In biology, the term most often refers to the addition of a methyl group to DNA or to proteins, often affecting gene activity or protein function.
- The chemical addition of a methyl group to a molecule, especially in biological systems.
- The process by which methyl groups are added to DNA, RNA, or proteins, often influencing gene regulation or molecular function.
"The researchers studied how methylation changes the activity of the gene during development."
"Methylation of the gene is associated with reduced expression in the affected cells."
"The laboratory uses a methylation assay to identify chemically modified DNA regions."
The plural refers to multiple instances of the process, multiple forms of methylation, or distinct methylation patterns.
"The study compared the methylations of several genes across the two groups."
Methylation helps switch genes on and off without changing their underlying DNA sequence.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does methylation come from?
The word is formed from the chemical term methyl plus the suffix -ation, which indicates a process. Methyl itself comes from Greek methy-, associated with methē, meaning wine, and ultimately relates to the substance from which methyl alcohol was historically produced. The scientific sense developed through the terminology of organic chemistry before becoming especially important in molecular biology.
Related word forms
How methylation is actually used
The term is primarily technical, used in chemistry, molecular biology, genetics, and medicine. It is generally used with chemical or biological systems rather than in everyday conversation.
Easily confused with methylation
Methylation is a process involving the addition of a methyl group, whereas a methyl group is the chemical group itself.
A methyl group is a substituent containing one carbon atom and three hydrogen atoms, while methylation describes the process of attaching that group.