A quick swab of your cheek might one day reveal how long you have left to live. Researchers have discovered that a DNA test originally designed to measure biological aging from cells inside the cheek can accurately predict mortality risk, even when applied to blood samples. The findings suggest that common biological markers of aging exist across different tissues in the body, potentially opening new avenues for assessing health risks and developing anti-aging interventions.
The study centers on a tool called CheekAge, a next-generation “epigenetic clock” developed earlier this year. Our genes contain the instructions for building and maintaining our bodies, but how these genes are read and expressed can change over time. One way this happens is through a process called DNA methylation, where small chemical tags attach to our DNA. These tags act like switches, turning genes on or off.
Most previous epigenetic clocks relied on blood samples, making them less practical for widespread use. CheekAge, as its name implies, was designed to work with easily collected cheek cells. What makes this new study particularly intriguing is that CheekAge proved effective at predicting mortality risk even when applied to blood sample data.
To test this, they turned to a unique dataset from Scotland called the Lothian Birth Cohorts. This long-running study has been following two groups of people born in 1921 and 1936, collecting detailed health information and biological samples over many years.
Using blood samples from 1,513 participants (712 men and 801 women) between the ages of 67 and 90, the team applied their CheekAge algorithm. Even though CheekAge was designed for cheek samples and nearly half of its DNA markers weren’t present in the blood data, it still showed a strong ability to predict mortality risk.
Specifically, for each standard deviation increase in the difference between a person’s CheekAge and their actual age, their risk of death increased by 21%. To put this in perspective, the researchers divided participants into three groups based on their CheekAge results. The group with the “oldest” biological age reached 50% mortality about 7.8 years earlier than the group with the “youngest” biological age.
What’s particularly impressive is that CheekAge performed better at predicting mortality than several other established epigenetic clocks. It even rivaled a specialized clock called DNAm PhenoAge, which was specifically designed to predict mortality using blood samples.
“The fact that our epigenetic clock trained on cheek cells predicts mortality when measuring the methylome in blood cells suggests there are common mortality signals across tissues,” explains Dr. Maxim Shokhirev, the study’s first author and Head of Computational Biology and Data Science at Tally Health, in a statement. “This implies that a simple, non-invasive cheek swab can be a valuable alternative for studying and tracking the biology of aging.”
The study, published in the journal Frontiers in Aging, also identified specific DNA markers that seemed especially important for mortality prediction. One standout was a marker associated with a gene called ALPK2. When this marker was removed from the analysis, the ability to predict mortality dropped significantly. Interestingly, ALPK2 has been linked to heart development in animal studies and may play a role in certain cancers.
“It would be intriguing to determine if genes like ALPK2 impact lifespan or health in animal models. Future studies are also needed to identify what other associations besides all-cause mortality can be captured with CheekAge,” says Dr. Adiv Johnson, the study’s last author and Head of Scientific Affairs and Education at Tally Health. “For example, other possible associations might include the incidence of various age-related diseases or the duration of ‘healthspan’, the period of healthy life free of age-related chronic disease and disability.”
Source: https://studyfinds.org/cheek-swab-predict-when-youll-die/?nab=0