Chuck Bednar for redOrbit.com – Your Universe Online
Chemical changes that take place in a person’s DNA as a person grows older could serve as a “biological clock” which could provide clues as to how long a person will live, according to new research published in the journal Genome Biology.
In the study, scientists from the University of Edinburgh and colleagues from Australia and the US report that these chemical changes can help predict a person’s age, and that they can compare that data with those individuals’ actual ages to predict how long those people will live.
Those people whose biological age, based on their DNA, was greater than their actual age were more likely to die sooner than those whose biological and actual ages were the same, according to four studies that tracked nearly 5,000 older people for periods of up to 14 years each.
The biological age of each individual was measured using a blood sample provided at the start of the study, and follow-ups were conducted throughout the course of the research. The authors found a correlation between a biological clock that tended to run faster and early death, and that link held true even after accounting for other factors such as smoking and cardiovascular disease.
The chemical modification, which is known as methylation, does not change a person’s DNA sequence. However, it does play a key role in biological processes, and can influence how genes are activated or switched off, the researchers said. Methylation changes can impact many genes and occur throughout a person’s life, and this information was used to measure biological age.
“The same results in four studies indicated a link between the biological clock and deaths from all causes,” said Dr. Riccardo Marioni from the University of Edinburgh’s Centre for Cognitive Aging and Cognitive Epidemiology (CCACE). “At present, it is not clear what lifestyle or genetic factors influence a person’s biological age. We have several follow-up projects planned to investigate this in detail.”
The use of methylation to determine a person’s biological age dates back to a 2012 study led by scientists at the University of California, San Diego School of Medicine, which described the markers and developed a model to quantify how aging occurs at the genetic and molecular level. The technique was said to provide researchers with a more precise method of determining how old a person is, as well as to predict and treat age-related diseases and other ailments.
“This new research increases our understanding of longevity and healthy ageing,” said lead investigator Professor Ian Deary, also from the CCACE. “It is exciting as it has identified a novel indicator of ageing, which improves the prediction of lifespan over and above the contribution of factors such as smoking, diabetes, and cardiovascular disease.”
—–
Follow redOrbit on Twitter, Facebook, Google+, Instagram and Pinterest.
Comments