methylcytosine

chemical compound

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July 20, 2026

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5-methylcytosine is a chemical compound formed when a methyl group is added to a cytosine residue in DNA. This process, known as DNA methylation, is crucial for regulating gene expression by controlling whether genes are turned on or off.1234

In bacteria and archaea, methylation acts as a defense mechanism, protecting their DNA from enzymes that could break it down. In higher organisms, including humans, 5-methylcytosine plays a vital role in development, cell differentiation, and silencing certain genes. Aberrant methylation patterns are linked to various diseases, including cancer.1432

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epigenomics
Research tools of epigenomics
The base 5′-methylcytosine is abundant in genomes, and some genomes and genomic regions contain more 5′-methylcytosines than others. The ability to identify the precise locations of such modified bases on a genomic scale was made possible by the development of a technique called bisulfite sequencing, which was…
Read More
The base 5′-methylcytosine is abundant in genomes, and some genomes and genomic regions contain more 5′-methylcytosines than others. The ability to identify the precise locations of such modified bases on a genomic scale was made possible by the development of a technique called bisulfite sequencing, which was…
Read More