New Research Reveals Potential Precision Medicine Blood Test for Determining an Individual’s Chronobiome

Testing an individual’s chronobiome one step closer to reality with new breakthrough

There are many facets to the concept of precision medicine and how it can be applied in clinical practice. Rather than exploring genetics alone, research out of Colorado University (CU) Boulder brings the circadian rhythm and its extension—the chronobiome—into focus.

Important to personalized medicine, a person’s circadian rhythm may influence disease symptoms that are experienced, how medications affect the body, and how the body functions. Circadian rhythm disruptions are thought to contribute to a variety of health issues, among them cardiac and neurological problems.

What makes circadian rhythm challenging for doctors and nurses is that it can vary by as much as four to six hours from person to person. This means that hormone levels, metabolic changes, and other biological functions fluctuate under the direction of a person’s chronobiome (a relatively new concept explained in 2017).

While biomes may be better understood with climate and nature, they are now being applied for function in human health. In other words, a person’s unique chronobiome affects medication dosing and timing, and can play a role in the development of chronic conditions, such as diabetes, hypertension, and cancer.

CU Boulder’s new research, which was published in July 2021, builds on recent research by providing a potential method for testing physiological changes that are influenced by a person’s unique chronobiome. With a better understanding of the chronobiome, doctors and pharmacists may be able to tailor treatment and medication plans so that timing is not only optimal but personalized.

New Chronobiome Research Compares Metabolites to Melatonin

Identifying mechanisms underlying health problems associated with circadian misalignment will help develop precision medicine countermeasures, stated authors of a research article published in 2018 in the Proceedings of the National Academy of Sciences.   

“If we can understand each individual person’s circadian clock, we can potentially prescribe the optimal time of day for them to be eating or exercising or taking medication. From a personalized medicine perspective, it could be groundbreaking,” said CU Boulder research Senior Author Christopher Depner, PhD, in a recent press release. Depner, who is also an author on the PNAS article, conducted the study while an assistant professor of integrative physiology at CU Boulder. Depner is now an assistant professor of kinesiology at the University of Utah.

Evaluating an individual’s chronobiome currently involves testing the individual’s levels of melatonin hourly. This is a process so complex and time consuming that it is impractical to test in clinical practice.

Christopher Depner, PhD (left), currently of the University of Utah, and Ken Wright, PhD (right), of Colorado University Boulder’s Sleep and Chronobiology Laboratory, expand on earlier research into the chronobiome. Depner’s and Wright’s work targets developing a blood test that could be used in routine practice.

For CU Boulder’s chronobiome research, Depner and his team studied 16 volunteers over a two-week period, measuring their melatonin hourly and analyzing hourly blood samples for 4,000 different metabolites. Researchers used a machine learning algorithm to compare metabolites to melatonin levels, identifying 65 metabolites that showed changes in levels corresponding to each individual’s circadian rhythm

While the initial results of CU Boulder’s chronobiome study will need to be further narrowed to create a simple clinical test, this research shows that determining an individual’s unique chronobiome with a simple blood test is possible.

Biomarkers for Circadian Rhythm

“If we want to be able to fix the timing of a person’s circadian rhythm, we need to know what that timing is,” said study co-author Ken Wright, PhD, a professor of integrative physiology and director of the Sleep and Chronobiology Laboratory at CU Boulder. “Right now, we do not have an easy way to do that. We are at the very beginning stages of developing these biomarkers for circadian rhythm, but this promising study shows it can be done.” 

Precision medicine advances in the area of the chronobiome will play an important role in the future treatment of patients. While this technology is still in its early days, hospital administrators should be aware of developments in this area. Once routinely testing individuals’ chronobiomes is clinically feasible, it will play an essential role in personalizing individuals’ medication administration, diet, and exercise—factors that play a role in patient outcomes.

—Caleb Williams

Related Information:

Identification of a Preliminary Plasma Metabolome-based Biomarker for Circadian Phase in Humans

A blood test for your body clock? It’s on the horizon

A Pilot Characterization of the Human Chronobiome

Hospital Administrators Will Need to Understand How the Chronobiome Could Impact Precision Medicine

Christopher Depner, PhD

Ken Wright, PhD