Steve Horvath
Professor of Medicine, Division of Geriatrics · Director of Aging Biology Research, Department of Medicine · David Geffen School of Medicine at UCLA
We study the biology of aging through epigenetic clocks: building biomarkers that measure biological age across tissues and species, and using them to test whether interventions can slow or reverse aging.
Dr. Steve Horvath is a geroscientist whose research bridges the fields of biomarkers, precision medicine, genomics, and comparative biology. He is Professor of Medicine and Director of Aging Biology Research in the Department of Medicine at the David Geffen School of Medicine, University of California, Los Angeles (UCLA). Widely recognized for his work on epigenetic aging clocks, Dr. Horvath developed the first multi-tissue epigenetic clock in 2013, which allows for the estimation of biological age across diverse human tissues. His research began with the first saliva-based epigenetic clock in 2011, continued with second-generation clocks for predicting mortality risk, and in 2023 produced the universal pan-mammalian clock: a single mathematical formula capable of measuring aging across all mammalian species. Beyond his academic research, Dr. Horvath founded the non-profit Epigenetic Clock Development Foundation. He has been named on Clarivate’s annual list of the world’s most influential scientific researchers every year since 2018.
Research
Epigenetic clocks
DNA methylation changes with age in a remarkably regular way. Epigenetic clocks are mathematical models that read those changes and estimate biological age, in humans across tissues and, since 2023, across all mammalian species.
Biomarkers of aging
A clock is only useful if it predicts something that matters. We build and validate biomarkers that track healthspan and mortality risk in large cohorts, and we study what they do and do not tell us about the underlying biology.
Epigenetic rejuvenation
If the epigenome records age, can it be reset? We use clocks to test whether reprogramming and small-molecule interventions genuinely move biological age, and we hold those tests to a high evidential bar.
Methods and software
The field can only measure biological age reproducibly if the tools are open. We publish the statistical methods and software behind our clocks so that other laboratories can apply, test, and improve them.
Selected publications
Six papers that define the program. Full list →