Researchers have linked abnormal DNA methylation to several adverse outcomes, including human diseases.
So far, much of this research has been focused on cancer and tumour suppressor genes, since hypermethylation often results in the silencing of tumour suppressor genes in cancerous cells.
Compared to normal cells, the genomes in cancer cells have also been shown to be hypomethylated over all, with hypermethylation only occurring in the genes involved in tumour cell invasion, cell cycle control, DNA repair and other processes where silencing would lead to the spread of cancer.
In colon cancer, it is possible to detect hypermethylation early on in the course of disease, meaning hypermethylation may serve as a biomarker for the condition.
https://www.news-medical.net/life-sciences/What-is-DNA-Methylation.aspx
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