# methylation

CEFR C1 · Noun

Source: https://englishreference.com/word/methylation
Updated: 2026-05-19

## Definition

a chemical process where a methyl group is added to a molecule. This often changes how the molecule behaves or reacts with other substances.

For teachers: the chemical process of adding a methyl group to a compound. This modification is fundamental in organic chemistry and biochemistry, particularly in the regulation of gene expression and the synthesis of various biomolecules.

## Examples

- The methylation of DNA can silence specific genes.
- Scientists are studying how environmental toxins affect the methylation of proteins in the liver.
- Epigenetic changes, such as the methylation of histone tails, play a critical role in determining which genes are expressed during the early stages of embryonic development.

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