CpG dinucleotide

genetics

Also known as: cytosine-phosphate-guanine dinucleotide

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July 20, 2026

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CpG dinucleotides are specific sequences in DNA where a cytosine (C) is immediately followed by a guanine (G). In vertebrates, methylation, the addition of a methyl group, primarily occurs at these CpG sites. This process is crucial for regulating gene expression, essentially acting as a switch to turn genes on or off.123

Methylation plays a significant role in various biological processes, including embryonic development and controlling gene activity. Aberrant methylation patterns are also linked to diseases like cancer. While most methylation happens at CpG sites, some non-CpG methylation also occurs, particularly in embryonic stem cells.23

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epigenomics
Research tools of epigenomics
…before guanine residues, in so-called CpG (cytosine-phosphate-guanine) dinucleotide pairs. This phenomenon appears to be explained by the fact that the enzymes in vertebrates believed to add methyl groups to cytosines recognize CpG dinucleotide pairs almost exclusively. In embryonic stem cells, however, 25 percent of methylcytosines are not in CpG dinucleotides;…
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…before guanine residues, in so-called CpG (cytosine-phosphate-guanine) dinucleotide pairs. This phenomenon appears to be explained by the fact that the enzymes in vertebrates believed to add methyl groups to cytosines recognize CpG dinucleotide pairs almost exclusively. In embryonic stem cells, however, 25 percent of methylcytosines are not in CpG dinucleotides;…
Read More