In our 2018 newsletter, we told you about our study concerning DNA methylation, a common natural process whereby methyl groups (each made up of one carbon atom and three hydrogen atoms) attach to sites in a gene’s DNA and alter the gene’s function. A methylated gene is ‘switched off’ and will not be active. Methylation is called an epigenetic rather than genetic mechanism because it regulates the function of genes in the body’s cells without changing their DNA sequence.
The relationship between DNA methylation and cancer is now a very active research topic. Two recent studies are good examples. In these studies, our researchers analysed DNA from Health 2020 participants’ blood samples, taken both at baseline and at the second round of follow-up (approximately 11 years later).
The researchers looked at whether, and to what degree, DNA methylation patterns are associated with smoking and with alcohol consumption. They identified many new associations between these two habits and DNA methylation and also showed that the methylation changes associated with them appeared largely reversible.
These studies add to existing findings of links between established cancer risk factors and DNA methylation and demonstrate that changing habits such as smoking and drinking – even later in life – could help reverse past damage, at least in part.
Dugué PA et al. Smoking and blood DNA methylation: an epigenomewide association study and assessment of reversibility. Epigenetics. 2020 Apr;15(4):358-368.
Dugué PA et al. Alcohol consumption is associated with widespread changes in blood DNA methylation: Analysis of cross-sectional and longitudinal data. Addict Biol. 2019 Dec 2:e12855.