NeoDarwinian Random Mutations are mostly Epigenetic Biased Mutations


The term "random mutations" is being replaced by "mutational bias" to reflect the fact that mutations are not truly random, but are instead influenced by a variety of factors, including epigenetics the chemical structure of DNA, the environment, and the organism's own genes.

For example, there is a well-known bias towards transitions (changes between the same base pairs, such as A to G or C to T) over transversions (changes between different base pairs, such as A to C or G to T). This is because the chemical structure of DNA makes transitions more likely than transversions.

There are also epigenetic mutational biases that are specific to certain organisms or genes.

The concept of mutational bias is important for understanding how evolution works. Mutations are the raw material for evolution, and the mutational bias determines which mutations are more likely to occur. This, in turn, affects the rate and direction of NonDarwinian (random mutation) evolution.

In recent years, there has been a growing appreciation of the importance of epigenetic mutational bias in evolution. This has led to a shift in the way that evolution is taught and studied. Instead of focusing solely on random mutations, scientists are now taking into account the mutational bias that shapes the process of evolution.

Here are some of the reasons why the term "random mutations" is being replaced by "mutational bias":

  • Mutations are not truly random. They are influenced by a variety of factors, including epigenetics, the chemical structure of DNA, the environment, and the organism's own genes.

  • Mutational bias can have a significant impact on the course of evolution. By influencing which mutations are more likely to occur, mutational bias can affect the rate and direction of NonDarwinian evolution.

  • The concept of mutational bias is important for understanding how evolution works. It is now being incorporated into evolutionary models and theories.

Epigenetic mutational bias is the increased likelihood of mutations occurring in certain regions of the genome due to epigenetic modifications. 

A recent study in Nature estimates that epigenetics directs over 90% of mutations showing they are not random rather they are biased, challenging 100 years of evolutionary dogma. 

Epigenetic modifications are chemical changes to DNA or histone proteins that do not change the underlying DNA sequence, but can affect how genes are expressed.

There are a number of different epigenetic modifications that can lead to epigenetic mutational bias. One example is DNA methylation, which is the addition of a methyl group to a DNA molecule. DNA methylation can silence genes by preventing them from being transcribed. If a gene is silenced by DNA methylation, it is less likely to mutate.

Another example of an epigenetic modification that can lead to epigenetic mutational bias is histone modification. Histones are proteins that DNA wraps around. Histone modifications can change the way that DNA is packaged, which can affect gene expression. For example, histone acetylation is associated with gene activation, while histone methylation is associated with gene silencing.

The study of epigenetic mutational bias is a growing field of research. As we learn more about this phenomenon, we may be able to develop new treatments for diseases.

Here are some additional things to keep in mind about epigenetic mutational bias:

  • The extent of epigenetic mutational bias varies depending on the type of epigenetic modification and the cell type.

  • Epigenetic mutational bias can be influenced by environmental factors, such as exposure to toxins or radiation.

  • Epigenetic mutational bias can be reversible, meaning that the effects of epigenetic modifications can be reversed by changing the environmental conditions.

Overall, epigenetic mutational bias is a complex phenomenon that is still being studied. However, it is clear that epigenetic modifications can play a role in the occurrence of mutations.


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