Definition
An epigenetic modification of DNA is the addition of a methyl (CH3) group to position 5 of a cytosine residue. The majority of methylation events in humans occur on cytosines that are located next to a guanine (5′-CpG-3′ dinucleotides).
Characteristics
DNA methylation results from the addition of a methyl (CH3) group to position 5 of a cytosine (Fig. 1). The addition of a methyl group by DNA methyltransferases is an epigenetic modification to DNA that is maintained after cell division and does not change the DNA sequence. 5′-CpG-3′ dinucleotides are not uniformly distributed in the human genome. CpG islandsare short stretches of DNA, usually located in promoter regions of genes, with an unusually high GC content and a significantly higher frequency of 5′-CpG-3′ dinucleotides compared to the rest of the genome. It is well accepted that DNA methylation is involved in gene regulation. Inhibition of transcription factor binding by methylation of the target sequence was the...
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References
Baylin SB, Herman JG, Graff JR et al (1998) Alterations in DNA methylation: a fundamental aspect of neoplasia. Adv Cancer Res 72:141–196
Costello JF, Fruhwald MC, Smiraglia DJ et al (2000) Aberrant CpG-island methylation has non-random and tumour-type-specific patterns. Nat Genet 24:132–138
Herman JG, Graff JR, Myohanen S et al (1996) Methylation-specific PCR: a noval PCR assay for methylation status of CpG island. Proc Natl Acad Sci U S A 93:9821–9826
Okano M, Bell DW, Haber DA et al (1999) DNA methyltransferases Dnmt3a and Dnmt3b are essential for de novo methylation and mammalian development. Cell 99:247–257
Rountree MR, Bachman KE, Baylin SB (2000) DNMT1 binds HDAC2 and a new co-repressor, DMAP1, to form a complex at replication foci. Nat Genet 25:269–277
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Plass, C. (2015). Methylation. In: Schwab, M. (eds) Encyclopedia of Cancer. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-27841-9_3684-2
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DOI: https://doi.org/10.1007/978-3-642-27841-9_3684-2
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Publisher Name: Springer, Berlin, Heidelberg
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