Epigenetic Drift

Definition

Epigenetic drift is the gradual accumulation of epigenetic differences between cells, tissues, or individuals over time. It can include changes in DNA methylation, histone modifications, chromatin organisation, and gene regulation that arise through ageing, environmental exposures, stochastic variation, and imperfect maintenance of epigenetic marks. [1] [2] [3]

Why It Matters in Ageing Research

Epigenetic drift matters because ageing is associated with increasing variability and disruption in epigenetic regulation. These changes can affect cell identity, genome stability, inflammation, cancer risk, tissue function, and the interpretation of epigenetic clocks. Epigenetic drift is related to epigenetic ageing, but it is not the same as a clock-based estimate of epigenetic age. [4] [5] [6]

Common Confusion

• Epigenetic drift is not the same as genetic drift; it involves changes in gene regulation, not changes in inherited DNA sequence frequencies.
• Epigenetic drift is not identical to epigenetic age, although methylation clocks may capture some age-related epigenetic change.
• Not all epigenetic change with age is random; some changes are predictable, tissue-specific, or linked to disease processes.

Related Reading

• Epigenetics
• DNA Methylation
• Epigenetic Age
• Chromatin

References

1. Fraga, M. F., et al. (2005). Epigenetic differences arise during the lifetime of monozygotic twins. https://doi.org/10.1073/pnas.0500398102
2. Feinberg, A. P., & Irizarry, R. A. (2010). Stochastic epigenetic variation as a driving force of development, evolutionary adaptation, and disease. https://doi.org/10.1073/pnas.1006183107
3. Teschendorff, A. E., et al. (2013). Age-dependent DNA methylation of genes that are suppressed in stem cells is a hallmark of cancer. https://doi.org/10.1186/gb-2010-11-10-r108
4. Pal, S., & Tyler, J. K. (2016). Epigenetics and aging. https://doi.org/10.1126/sciadv.1600584
5. Sen, P., Shah, P. P., Nativio, R., & Berger, S. L. (2016). Epigenetic Mechanisms of Longevity and Aging. https://doi.org/10.1016/j.cell.2016.02.050
6. Lopez-Otin, C., et al. (2013). The Hallmarks of Aging. https://doi.org/10.1016/j.cell.2013.05.039