According to the researchers at the University of North Carolina the reason for this effect could be explained by DNA methylation of genes in breast cancer tumours or peripheral blood. The study was published in the journal 'Cancer'. Methylation is a chemical modification wherein a methyl group acts like light switches along the DNA molecule turning some genetic activity on and some off. Chemical shifts in areas of DNA that are responsible for cell death damage and repair - such as occurs in methylation - are known to contribute to the development of cancer over time. Identifying the areas where these
