CpG methylation is maintained in human cancer cells lacking DNMT1

@article{Rhee2000CpGMI,
  title={CpG methylation is maintained in human cancer cells lacking DNMT1},
  author={Ina Rhee and Kam-wing Jair and Ray-Whay Chiu Yen and Christoph Lengauer and James Gordon Herman and Kenneth W. Kinzler and Bert Vogelstein and Stephen B. Baylin and Kornel E. Schuebel},
  journal={Nature},
  year={2000},
  volume={404},
  pages={1003-1007}
}
Hypermethylation is associated with the silencing of tumour susceptibility genes in several forms of cancer; however, the mechanisms responsible for this aberrant methylation are poorly understood. The prototypic DNA methyltransferase, DNMT1, has been widely assumed to be responsible for most of the methylation of the human genome, including the abnormal methylation found in cancers. To test this hypothesis, we disrupted the DNMT1 gene through homologous recombination in human colorectal… 
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