In DNA methylation, small chemical groups are tagged on to the DNA to control expression. This can be used to suppress viral DNA, or to modify normal gene expression. DNA methylation is also involved in the development of cancer, including breast cancer, and may have potential as a blood biomarker to show the risk of developing the disease, according to two recent papers.
In a study in The FASEB Journal, a team of researchers in the U.S. and China used assays to screen blood from a case-control study (a study comparing women with and without breast cancer), and found links between high levels of methylation and increased risk of breast cancer.
In a separate study in Cancer Research, European researchers analyzed blood samples from women at high risk of breast cancer, and from other case-control studies, this again linked higher levels of methylation with increased risk of breast cancer.
Epigenetics is the study of all the changes in the DNA that do not occur as a result of changes in the DNA sequence, such as DNA methylation. A number of epigenetic changes have been linked with cancer, and as the area evolves, it could provide a rich seam of biomarkers for diagnosis, prognosis, progression and treatment progress.