The Epigenome includes a variety of epigenetic marks and modifications that occur on the DNA and surrounding histones and regulate gene expression without changing the DNA sequence itself. This makes it possible to distinguish a heart cell from a kidney cell, even if both have the same genetic material. It is a dynamic and highly complex regulatory system that controls gene activity and thus influences cell differentiation, development and adaptation to environmental stimuli. As an analogy, you can imagine that there are different volume controls placed around the DNA that make genes quieter (inactive) or louder (active).
How is the epigenome structured?
The epigenome consists of various epigenetic marks, including DNA methylation, post-translational modifications of histones and non-coding RNAs. DNA methylation refers to the addition of methyl groups to cytosine residues in CpG dinucleotide regions, while histones can be altered by acetylation, methylation, phosphorylation, and other modifications. These epigenetic modifications act together to modulate chromatin structure and thereby affect the accessibility of DNA to the transcription machinery.
To stay with the analogy. The methylations influence the volume controls and the histones are large proteins around which the DNA is wound. The best way to imagine this is like hair curlers. This makes whole sections either easier or harder to reach.
What does the epigenome have to do with age?
The epigenome undergoes changes over the course of life, which are referred to as epigenetic aging are known. Research has shown that epigenetic changes may be linked to age-related diseases such as cancer, heart disease and neurodegenerative diseases. In addition, environmental factors such as diet, stress and exposure to toxins can influence epigenetic changes and thus accelerate or slow down the aging process. Epigenetic factors also partly explain the difference between the Health span and life span.
Epigenome, epigenetics and epigenetic age – what is the difference?
To shed some light on the subject, we will clarify the most important terms once again. Epigenome refers to the totality of epigenetic marks in a cell or an organism. Epigenetics is the scientific discipline that studies these epigenetic mechanisms and changes. Epigenetic age is a measure that quantifies epigenetic changes over time and is often used as a measure of the biological aging process.
How can you measure the epigenome?
In science, there are various methods for measuring the epigenome, the analysis of DNA methylation patterns, as used by Nobel Prize winner Steve horvath to measure biological age. With the help of the Horvath Clock, he was able to Identify 353 locations on DNAthat correlate with biological age.
What are epigenome measurements used for in science?
Epigenomic analyses have broad applications in science. They are used to to decipher the molecular mechanisms of diseases, to investigate the effects of environmental factors on gene expression, to explore the genetic and epigenetic basis of development and differentiation, and even to carry out forensic analyses to identify perpetrators or genetic relationships. The findings from epigenomic studies contribute to the development of new diagnostic and therapeutic approaches for a wide range of diseases and help to deepen our understanding of health and disease at the molecular level.
One exciting aspect is that certain epigenetic patterns are hereditary. However, more research is needed on this.
Sources
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- Ceribelli, Angela, and Carlo Selmi. “Epigenetic Methods and Twin Studies.” Advances in experimental medicine and biology vol. 1253 (2020): 95-104. Link
- Sapienza, Carmen, and Jean-Pierre Issa. “Diet, Nutrition, and Cancer Epigenetics.” Annual review of nutrition vol. 36 (2016): 665-81. Link
- de Lima Camillo, Lucas Paulo, and Robert BA Quinlan. “A ride through the epigenetic landscape: aging reversal by reprogramming.” GeroScience vol. 43,2 (2021): 463-485. Link
- Applegate, Jason S, and Diane Gronefeld. “Factor V suffering.” Radiologic technology vol. 90,3 (2019): 259-273. Link
- Fides Zenk et al.“Germ line–inherited H3K27me3 restricts enhancer function during maternal-to-zygotic transition.” Science357,212-216(2017). Link
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