Understanding the complexities of epigenetic aging clocks in health research

Aging-USAug 14 2024

A new editorial was published in Aging (listed by MEDLINE/PubMed as "Aging (Albany NY)" and "Aging-US" by Web of Science), Volume 16, Issue 14 on July 17, 2024, entitled, "Recalibrate concepts of epigenetic aging clocks in human health."

As detailed in the opening of this editorial, DNA methylation-based epigenetic clocks are used as biomarkers of biological age in human health. Multiple epigenetic clocks have rapidly emerged in the past decade by modeling DNA methylation changes with age in large cohorts, primarily using peripheral blood samples. Despite efforts to understand the functional implications of features used to estimate biological age, the underlying mechanisms of these clocks remain poorly understood, leading to potential misinterpretations of their associations with health outcomes.

Researchers Ze Zhang, Brock C. Christensen, and Lucas A. Salas from the Divisions of Population Sciences and Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, the Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Dartmouth Cancer Center, Dartmouth-Hitchcock Medical Center, and the Department of Molecular and Systems Biology, Geisel School of Medicine, Dartmouth College explored the association of 12 immune cell types with epigenetic age acceleration (EAA) in both healthy and diseased populations. 

Their work sheds light on the complex interplay between immune cell composition and epigenetic aging, utilizing high-resolution methylation cytometry in blood samples.

"In this editorial, we aim to address the key implications of our study on epigenetic aging clocks in human health from a broader perspective. While epigenetic clocks are widely hyped as aging biomarkers today, it's essential to recalibrate some fundamental concepts in this field."