This is an excellent study, with exceptional technical quality and a high degree of conceptual innovation.

The study describes a new single-cell methodology based on epigenetics to better understand cell maturation from stem cells and how this process is altered during ageing and can lead to diseases such as cancer.

[Regarding potential limitations] As with any novel study, the promises outweigh the limitations. This work paves the way for other researchers in multiple fields of biomedicine. For now, no clinical applications are anticipated, but its potential for research is enormous.

This landmark study represents a major advance in our ability to understand and monitor ageing at the cellular level. Since ageing is the leading risk factor for a wide range of  diseases —including cancer and neurodegeneration—i t will be interesting to explore how EPI-Clone barcodes shift not only during healthy ageing, but also in the preclinical stages of  disease, before symptoms emerge and when interventions are most likely to be effective.

As such, EPI-Clone could become a valuable tool for assessing the efficacy of emerging anti-ageing therapies, such as senolytics.