Posted on Mar 23, 2017, 6 a.m.
New research reveals that an altered methylation status in the genome may indicate that mortality is increased by up to seven times
In a recent study from the German Cancer Research Center, scientists are pursuing the mortality risks of people who undergo methylation of their DNA which can determine a person's health status. Modification of genes in the genome can lead to genes being turned on or off which can lead to diseases like cancer. The main culprit in turning off genes is methylation, as there are already well-documented studies linking methylation and some diseases. Risk factors for this phenomenon include smoking which can deactivate critical genes, or turn on undesirable ones.
58 Methylated DNA Building Blocks Identified
The aim of the research was to determine if higher levels of methylation had any correlation to mortality. In the 14 year study, 1900 older adults participated, providing blood samples in which the researchers extracted their DNA. The building blocks of DNA (called CpGs), consist of about a half million positions in the genome. Researchers had a rigorous task of finding only those CpG blocks that methyl groups are able to attach to. They found 58 methylated CpGs related to the participants higher mortality rates since many had died since the study began.
Smoking appears to have the strongest impact on the health of the genome and of the 58 CpGs found by the researchers, these DNA building blocks when altered were all associated with many different diseases. In fact, researchers found that 22 out of the 58 CpGs were previously associated with methylation caused by smoking in earlier studies. However, not all is lost as DNA methylation is reversible if people stop smoking. Researchers think the mortality risk could drop dramatically after cessation of smoking.
Ten DNA Positions Responsible For Higher Mortality
Scientists went on to discover that 10 of the 58 CpGs were prime culprits in higher mortality risks associated with cardiovascular disease and cancer. In the study, participants with a compromised genome due to methylation of their DNA had a mortality risk seven times higher than those participants who showed no abnormal DNA.
The researchers were surprised that only ten positions in our genome are responsible for so many diseases and higher mortality rates. But methylation has proven to be the most damaging alteration to our DNA. The 10 most significant CpGs are proving to be the most accurate of all established epigenetic risk profiles used to predict individual life spans. Now comes the important research into finding the most effective preventative measures to protect our DNA from methylation and increase our potential life span.
an Zhang, Rory Wilson, Jonathan Heiss, Lutz P. Breitling, Kai-Uwe Saum, Ben Schöttker, Bernd Holleczek, Melanie Waldenberger, Annette Peters, Hermann Brenner. DNA methylation signatures in peripheral blood strongly predict all-cause mortality. Nature Communications, 2017; 8: 14617 DOI: 10.1038/ncomms14617