NeoDarwinian mutations - no longer "random"

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Neo-Darwinism views DNA polymerase errors as one of the main sources of variation. DNA polymerase is an enzyme that replicates DNA during cell division. Sometimes, DNA polymerase can make mistakes, which can lead to changes in the DNA sequence. These changes are called mutations.

Most mutations are harmful or neutral, but a few can be beneficial. Beneficial mutations can give an organism an advantage over other organisms, which can help it to survive and reproduce. Over time, this can lead to the evolution of new species.

DNA polymerase errors are thought to be one of the most important sources of NeoDarwinian variation, as they can occur at any time during the life cycle of an organism. This means that there is a constant supply of new mutations that can be acted upon by natural selection.

DNA polymerase errors play a significant role in NeoDarwinian evolution. These errors can lead to new mutations, which can provide organisms with new opportunities to adapt to their environment.


GC bias above

GC bias, mutation bias, and DNA polymerase errors are all factors that can contribute to the overall mutation rate in a genome. GC bias and mutation bias are NonDarwinian processes as they can occur outside of meiosis. 

The relative contribution of each of these factors to the overall mutation rate in a genome varies depending on the organism and the environment. In general, GC bias is thought to be the most important factor in determining the overall mutation rate, followed by mutation bias and then DNA polymerase errors.

GC bias contributes 50-60%. Mutation bias 30-40%. DNA polymerase mutations <1%.

Please note that these numbers are just estimates and the actual percentages may vary depending on the specific organism and environment however it's clear DNA polymerase errors are a minor player.

There is growing evidence that DNA polymerase errors can be controlled by epigenetics in a non random fashion. Epigenetics refers to changes in gene expression that do not involve alterations to the DNA sequence itself. These changes can be caused by a variety of factors, such as environmental exposures, diet, and lifestyle. Epigenetic modifications can affect DNA polymerase activity in several ways. For example, they can alter the accessibility of the DNA to the polymerase, or they can modify the polymerase itself. These changes can lead to changes in the rate of DNA replication and the fidelity of DNA synthesis. The role of epigenetics in controlling DNA polymerase errors is still being investigated, but it is clear that these modifications can play a significant role in maintaining the integrity of the genome. Here are some specific examples of how epigenetics can control DNA polymerase errors:

  • DNA methylation: DNA methylation is the addition of a methyl group to a DNA base. This modification can affect DNA polymerase activity by altering the structure of the DNA and making it more or less accessible to the polymerase.

  • Histone modifications: Histones are proteins that package DNA into chromatin. Histones can be modified in a variety of ways, including acetylation, methylation, and phosphorylation. These modifications can affect DNA polymerase activity by altering the accessibility of the DNA to the polymerase and by recruiting other proteins to the chromatin.

  • Non-coding RNAs: Non-coding RNAs are RNAs that do not code for proteins. Some non-coding RNAs can interact with DNA polymerase and affect its activity.

The study of epigenetics is a rapidly growing field, and it is likely that we will learn more about the role of epigenetics in controlling DNA polymerase errors in the years to come.

DNA polymerase errors are no longer considered to be random mutations. This is because research has shown that these errors are not evenly distributed across the genome. Instead, they are more likely to occur in certain regions, such as regulatory elements. This suggests that DNA polymerase errors are not accidents, but rather is a part of a process that helps organisms adapt to their environment. Studies show biased mutations can make the DNA polymerase less accurate, which means that it is more likely to make errors. These errors are beneficial, as they can lead to new genes or changes in existing genes that help the bacteria to survive. This suggests that DNA polymerase errors may play a role in rapid NonDarwinian adaptation. This is a type of adaptation that does not require the gradual accumulation of mutations over time. Instead, it can occur in a single generation. This is because moderated DNA polymerase errors can create new genes or change existing genes in a single step. This type of adaptation may be important for organisms that need to adapt quickly to new environments. For example, bacteria that are exposed to antibiotics need to find a way to resist the drugs quickly. DNA polymerase errors can help them to do this by creating new genes that make them resistant to the antibiotics. Overall, it is clear that DNA polymerase errors are not random mutations. They are more likely to occur in certain regions of the genome, and they may play a role in rapid NonDarwinian adaptation. This is an important finding, as it suggests that there may be more to mutation than we previously thought. 

It also suggests neo darwinism needs modification or replacement.

Ref

GC bias

Mutation bias

DNA polymerase errors

Epigenetics DNA polymerase


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