Methylations

Part of speech: noun

Pronunciation: /ˌmɛθɪˈleɪʃənz/

Definitions

1. The process of adding a methyl group to a DNA molecule, which can regulate gene expression without changing the DNA sequence
2. The biochemical modification involving the attachment of a methyl group to a substrate, influencing various metabolic processes
3. Alterations in gene expression through the addition of methyl groups, impacting cellular functions and development

Etymology: Methylations is simply the plural of methylation, and the word's history runs through chemistry rather than folklore. It is built from "methyl," the name of the one-carbon group CH3, combined with the English suffix "-ation," which turns a verb into a noun for a process, as in "oxidation" or "reduction." The name "methyl" was formed in German as "Methyl," and English adopted it as "methyl." Its ultimate source is the Greek "méthu," meaning wine, with "hū́lē," meaning wood or matter, the two elements joining to suggest a substance derived from wood spirit, the alcohol then called methyl alcohol. The "-ation" ending came into English through Old French from Latin "-ātiō," a route it shares with countless other process nouns. In biology, the sense narrowed to adding a methyl group to DNA. Methylation of this kind can switch genes off or on without altering the underlying sequence of bases, which is why the plural is now used when researchers compare many such chemical changes across a genome.