New molecular test can reveal biological age

A new molecular test, which can indicate the unique rate at which a person is ageing, could transform the way ageing is approached in medical research by assessing a person’s ‘biological age’ rather than the number of years one has lived. The findings, published the journal Genome Biology, could help manage age-related disease by identifying people most at risk of diseases affected by age, as well as improve the way anti-ageing treatments are evaluated.

The seven-year collaborative study at King’s College London, Karolinska Institutet and Uppsala University in Sweden, and Duke University in the USA, used a process called RNA-profiling to measure and compare gene expression in thousands of human tissue samples. Rather than look for genes associated with disease or extreme longevity, the researchers discovered that the ‘activation’ of 150 genes in the blood, brain and muscle tissue were a hallmark of good health at 65 years of age.

After discovering that it was the levels of the exact same genes that were regulated in very different types of tissue, the researchers were able to create a formula for ‘healthy ageing’, and use this test to tell how well a person is ageing when compared to others born the same year.

The extensive range in ‘biological age’ scores of people born at the same time indicates that a person’s biological age is separate and distinct to his/her chronological age.

Lower cognitive status

Importantly, a low score was found to reflect lower cognitive status, with low levels of gene expression measured in the blood also reflecting regulation of the same genes in brain regions involved with neurodegeneration. These findings imply that the molecular test could translate into a simple blood test to predict those most at risk of Alzheimer’s disease and suitable for taking part in prevention trials.

The Swedish part of this study was supervised by Dr Thomas Gustafsson, MD, PhD, Associate Professor at the Department of Laboratory Medicine, Karolinska Institutet. The project was funded by the Swedish Research Council, the Wallenberg Foundation, Sweden, the Medical Research Council (MRC), UK, National Institutes of Health (NIH), US, and the Innovative Medicines Initiative (IMI), a joint undertaking between the European Union and the pharmaceutical industry association EFPIA. This news article is an abbreviation of a press release from MRC.

Publication

A novel multi-tissue RNA diagnostic of healthy ageing relates to cognitive health status
Sanjana Sood, Iain J Gallagher, Katie Lunnon, Eric Rullman, Aoife Keohane, Hannah Crossland, Bethan E Phillips, Tommy Cederholm, Thomas Jensen, Luc JC van Loon, Lars Lannfelt, William E Kraus, Philip J Atherton, Robert Howard, Thomas Gustafsson, Angela Hodges and James A Timmons
Genome Biology 2015, 16:185, online 7 September 2015, doi:10.1186/s13059-015-0750-x