"The fit thrive" not the "survival of the fittest."
Title: "The fit thrive" not the "survival of the fittest."
"It is doubtful, however, whether even the most
statistically minded geneticists are entirely satisfied that nothing more is involved than the sorting out of random mutations by the natural selective filter." - Conrad Waddington, father of Epigenetics, Letter to Nature journal the year the MS (theory of evolution) was released in '42
DNA polymerase errors are responsible for about 10-20% of DNA substitutions. DNA polymerases are enzymes that copy DNA during replication. They are very accurate, but they do make mistakes occasionally. These mistakes can lead to DNA substitutions, which are changes in the base sequence of DNA.
DNA polymerases have built-in proofreading mechanisms that can correct most of the errors they make. However, some errors still escape proofreading and can lead to DNA substitutions.
The percentage of DNA substitutions due to polymerase errors varies depending on the type of DNA polymerase and the environmental conditions. DNA substitutions can have a variety of consequences. Some substitutions may be "silent", meaning that they do not change the amino acid sequence of the protein that is encoded by the DNA.
Although last year this was disproved. The majority of "silent," mutations are harmful.
Other substitutions may be harmful, leading to diseases or developmental disorders.
In addition to DNA polymerase errors, other factors that can cause DNA substitutions include:
Environmental damage, such as exposure to UV radiation or chemicals
Errors in DNA repair, such as when a DNA repair enzyme fails to repair a damaged nucleotide
Transposition, which is the movement of DNA sequences within a genome.
Epigenetics, below.
Random DNA substitutions by DNA polymerases are an axiom of NeoDarwinism. Darwinists hold that this is the random "variation" Darwin proposed in the Oos for natural selection to act on.
DNA polymerase errors are also controlled by epigenetics. Epigenetic modifications, such as DNA methylation and histone modifications, can affect DNA accessibility and the recruitment of DNA repair proteins, which can ultimately impact DNA polymerase fidelity.
Studies suggest that epigenetic modifications can play a major role in regulating DNA polymerase expression and fidelity.
There is other evidence that suggests that epigenetics may play a role in controlling DNA polymerase errors:
Epigenetic modifications can affect the recruitment of DNA repair proteins, such as mismatch repair proteins. Mismatch repair proteins are responsible for correcting errors that occur during DNA replication. If mismatch repair proteins are not recruited to a site of DNA damage, the error may not be corrected and may be passed on to the next generation of cells.
Epigenetic modifications can also affect the chromatin structure, which can impact the accessibility of DNA to DNA polymerases. If DNA is not accessible to DNA polymerases, it is more likely that errors will occur during replication.
Overall, the evidence suggests that epigenetics play a significant role in controlling Darwins DNA polymerase errors.
AT mutation bias is a tendency of genomes to mutate towards a higher AT content. This is a common phenomenon in all living organisms, from bacteria to humans.
The percentage of DNA substitutions due to AT mutation bias varies depending on the organism and the specific gene being considered. However, studies have shown that AT mutation bias can account for anywhere from 20% to 60% of all DNA substitutions.
For example, a study of human genes found that AT mutation bias accounted for about 50% of all DNA substitutions. Another study of yeast genes found that AT mutation bias accounted for about 50% of all DNA substitutions.
AT mutation bias is caused by a number of factors, including:
The DNA replication machinery is more likely to make mistakes when copying AT-rich DNA. This is because AT pairs have 2 hydrogen bonds versus GC pairs with 3 h bonds.
AT-rich DNA is more likely to be damaged by environmental factors such as UV light.
AT-rich DNA is less likely to be repaired by DNA repair enzymes.
AT mutation bias can have a number of consequences, including:
It can lead to the accumulation of harmful mutations in genes, which can increase the risk of cancer and other diseases.
It can also lead to changes in gene expression, which can affect a wide range of cellular processes including rapid adaptation.
Overall, AT mutation bias is a significant contributor to DNA substitutions in all organisms. However, the percentage of DNA substitutions due to AT mutation bias varies depending on the organism and the specific gene being considered.
Studies suggest 20-30% of all DNA substitutions in humans are due to gBGC bias. This means that about 1 in every 5-10 DNA mutations is caused by this type of bias.
gBGC bias is a type of mutational bias that occurs when the DNA repair system is less likely to repair mutations that occur in certain sequences of DNA. These sequences are typically rich in the nucleotides guanine (G), cytosine (C), and adenine (A).
gBGC bias has been shown to play a role in the development of a number of diseases, including cancer, autism, and schizophrenia. It is also thought to contribute to the aging process.
However, it is important to note that gBGC bias is not the only cause of DNA mutations.
We've gone from hardened NeoDarwinism with completely random mutations due to DNA polymerase errors to nonrandom "biased" substitutions.
Dennis Noble discusses "biased mutations" here in one minute
Indeed DNA polymerase mutations once thought to be in the back "pocket" of Darwin are now known to be in Lamarck's epigenetics back "pocket."
AT mutation bias, GC bias (gBGC) and epigenetics control the majority of "substitutions."
The term "substitution" overcomes the term "mutation" with its Darwinian baggage. Substitutions are naturally occurring changes for "biased" adaptation without Darwin.
Instead of "survival of the fittest" we have the "fit that thrive" for adaptation.
It's almost like there was some force that made it possible for organisms to "thrive" over the life of our planet.
Now who would have thought of that!?
Psalms 104:
"O Lord, how many are Your works! In wisdom You have made them all; The earth is full of Your possessions."
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