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bioRxiv · 10.1101/2020.02.05.927434

Quantification of the pace of biological aging in humans through a blood test: a DNA methylation algorithm

Abstract

Biological aging is the gradual, progressive decline in system integrity that occurs with advancing chronological age, causing morbidity and disability. Measurements of the pace of aging are needed to serve as surrogate endpoints in trials of therapies designed to prevent disease by slowing biological aging. We report a blood DNA-methylation measure that is sensitive to variation in the pace of biological aging among individuals born the same year. We first modeled longitudinal change in 18 biomarkers tracking organ-system integrity across 12 years of follow-up in the Dunedin birth cohort. Rates of change in each biomarker were composited to form a measure of aging-related decline, termed Pace of Aging. Elastic-net regression was used to develop a DNA-methylation predictor of Pace of Aging, called DunedinPoAm for Dunedin (P)ace (o)f (A)ging (m)ethylation. Validation analyses showed DunedinPoAm was associated with functional decline in the Dunedin Study and more advanced biological age in the Understanding Society Study, predicted chronic disease and mortality in the Normative Aging Study, was accelerated by early-life adversity in the E-risk Study, and DunedinPoAm prediction was disrupted by caloric restriction in the CALERIE trial. DunedinPoAm generally outperformed epigenetic clocks. Findings provide proof-of-principle for DunedinPoAm as a single-time-point measure of a persons pace of biological aging.

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BibTeXRIS

Belsky, D. W., Caspi, A., Arseneault, L., Corcoran, D. L., Hannon, E., Harrington, H. L., Hartmann-Rasmussen, L. J., Houts, R., Huffman, K., Kraus, W. E., Mill, J., Pieper, C., Prinz, J., Poulton, R., Sugden, K., Williams, B., Moffitt, T. E.. 2020-02-07. Quantification of the pace of biological aging in humans through a blood test: a DNA methylation algorithm. https://doi.org/10.1101/2020.02.05.927434

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