Source:http://linkedlifedata.com/resource/umls/id/C1512554
NCI: Hypermethylation appears to be a controlled, epigenetic, heritable, and aberrant DNA methylation reaction on gene promoter regions and CpG islands associated with loss of (e.g., tumor-suppressor) gene function in diverse cellular pathways through transcriptional silencing by the formation of transcriptionally repressive chromatin.