The Quest for Markers of Biological Age

The substantial rise in life expectancy over the past century has not been matched by an equivalent increase in healthy lifespan. This leaves us with a problem: as the population continues to age, the burden of chonic diseases of ageing becomes ever greater.

If we are to address this challenge, we must first identify measurable biomarkers that will allow us to predict the adverse outcomes of ageing on an individual basis, and thus intervene in a timely fashion. This review sets out the main hallmarks of ageing – the biological changes thought to underlie and drive diseases of age – and suggests an optimal biomarker for each hallmark based on current literature.

New hallmarks and biomarkers may emerge, especially with the advent of ”omic” approaches that can be used to measure a very large number of potential biomarkers and search for associations.

Giving the complexity of the aging process, the probability that a single biomarker will ever meet those ideal criteria seems very low. At the opposite, the availability of “omics” approaches now allows hypothesis-free identification of potential biomarkers, not only among genes, transcripts and proteins, but also among non-coding RNA and metabolites.