Epigenetics works with and without mutations


Typically epigenetic regulation is the control of gene expression without changes to the DNA sequence itself as opposed to random mutations with neo darwinism. It is mediated by a variety of chemical modifications to DNA and histones, as well as by the non-coding RNA molecules that interact with them. Epigenetic regulation plays a crucial role in all aspects of development and cellular function, and its dysregulation is associated with a wide range of diseases, including cancer.

However epigenetics also controls mutations. One of the most important ways that epigenetic regulation controls mutation is by influencing the accessibility of DNA to DNA repair enzymes. For example, DNA methylation, which is the addition of a methyl group to the cytosine base, can block the binding of DNA repair enzymes to damaged DNA. This makes it more likely that the damage will result in a permanent mutation.

Another way that epigenetic regulation controls mutation is by influencing the expression of genes involved in DNA replication and repair. For example, hypermethylation of the promoter region of a DNA repair gene can silence the gene, reducing the cell's ability to repair DNA damage.


Epigenetic regulation can also influence the mutation rate by affecting the chromatin structure. Chromatin is a complex of DNA and proteins that controls how DNA is packaged and regulated. Changes in chromatin structure can make DNA more or less accessible to DNA repair enzymes and other proteins that protect DNA from damage.


For example, histone modifications can alter the chromatin structure, making it more or less condensed. Condensed chromatin is less accessible to DNA repair enzymes, which can lead to an increased biased mutation rate.

Finally, epigenetic regulation can control mutation by influencing the activity of transposable elements. Transposable elements are mobile pieces of DNA that can insert themselves into new locations in the genome. When a transposable element inserts itself into a gene, it can disrupt the gene's function or even cause a guided mutation.

Epigenetic mechanisms can suppress the activity of transposable elements, preventing them from causing mutations. However, epigenetic dysregulation can lead to the activation of transposable elements, increasing the biased mutation rate.

Overall, epigenetic regulation plays a major role in controlling biased mutation. By understanding the epigenetic mechanisms that control mutation, we may be able to develop new strategies for preventing and treating diseases such as cancer.

Here are some specific examples of how epigenetic regulation controls mutation in cancer:

  • DNA methylation: DNA methylation is a common epigenetic modification that is frequently altered in cancer cells. Hypermethylation of promoter regions can silence tumor suppressor genes, while hypomethylation of repetitive DNA can lead to increased genomic instability and the activation of oncogenes.

  • Histone modifications: Histone modifications can also be altered in cancer cells. For example, histone acetylation is associated with gene activation, while histone deacetylation is associated with gene repression. Cancer cells often have decreased levels of histone acetylation, which can lead to the silencing of tumor suppressor genes.

  • Non-coding RNAs: Non-coding RNAs, such as microRNAs and long non-coding RNAs, can also play a role in regulating mutation in cancer. For example, microRNAs can silence genes involved in DNA repair, while long non-coding RNAs can regulate the expression of transposable elements.

By understanding the epigenetic mechanisms that control mutation in cancer, we may be able to develop new strategies for preventing and treating this disease. For example, epigenetic drugs that target DNA methylation, histone modifications, or non-coding RNAs are currently being investigated for the treatment of cancer.

Here are some ways in which the fact that the majority of mutations are under epigenetic control challenges neo darwinism:

  1. Epigenetic changes are much faster than genetic mutations. This means that epigenetic changes can lead to rapid adaptation, even without waiting for genetic mutations to occur. This is in contrast to neo darwinism, which emphasizes the importance of random genetic mutations in driving evolution.

  2. Epigenetic changes can be inherited across generations. This means that offspring can inherit the epigenetic changes that their parents acquired during their lifetime. This is in contrast to neo darwinism, which holds that only genetic mutations could be inherited.

  3. Epigenetic changes can be reversible. This means that epigenetic changes can be turned on and off, depending on the environment. This is in contrast to neo darwinism, which holds that genetic mutations were permanent and irreversible.

  4. Epigenetic changes can be coordinated across the genome. This means that epigenetic changes can affect the expression of multiple genes at once. This is in contrast to neodarwinism, which traditionally focused on the effects of individual genetic mutations.

  5. Epigenetic changes can be environmentally responsive. This means that epigenetic changes can be influenced by factors such as diet, stress, and exposure to toxins. This is in contrast to neodarwinism, which traditionally emphasized the role of random genetic mutations in driving evolution.

  6. Epigenetic changes can play a role in Lamarckian inheritance. Lamarckian inheritance is the idea that acquired traits can be inherited by offspring. Epigenetic changes provide a possible mechanism for Lamarckian inheritance, as epigenetic changes can be acquired during a lifetime and then passed down to offspring.

  7. Epigenetic changes can play a role in evolution without being selected for. This is because epigenetic changes can be neutral or even harmful, and they can still be inherited by offspring. This is in contrast to neodarwinism, which emphasizes the role of natural selection in driving evolution.

  8. Epigenetic changes can help to explain the rapid evolution of complex traits. Complex traits, such as human intelligence, are thought to be influenced by many different genes. Epigenetic changes can provide a way for these genes to be coordinately regulated, which could help to explain the rapid evolution of complex traits.

Overall, the discovery that the majority of mutations are under epigenetic control has challenged several of the core tenets of neodarwinism. It is still too early to say how neodarwinism will ultimately be modified to accommodate these new findings, but it is clear that epigenetics will play an important role in our understanding of evolution.

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