Biologically Active Substance
CpG island
Subclass of:
Genome Components; GC Rich Sequence
Definitions related to cpg islands:
  • Area of increased density of dinucleotide sequence guanine- phosphate diester-cytosine; unmethylated; site of frequent mutations; may be associated with constitutively expressed housekeeping genes.
    CRISP Thesaurus
    National Institutes of Health, 2006
  • Short region of DNA in which the frequency of the CG sequence is higher than in other regions.
    NCI
    U.S. National Cancer Institute, 2021
  • Areas of increased density of the dinucleotide sequence cytosine--phosphate diester--guanine. They form stretches of DNA several hundred to several thousand base pairs long. In humans there are about 45,000 CpG islands, mostly found at the 5' ends of genes. They are unmethylated except for those on the inactive X chromosome and some associated with imprinted genes.
    NLM Medical Subject Headings
    U.S. National Library of Medicine, 2025
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