De novo gene birth challenges Neo-Darwinism


“The waiting time for a pair of pre-specified mutations was calculated by Durrett and Schmidt, using a Drosophila mutation that inactivates a transcription factor as their model. Their results, which are strongly dependent on assumptions about nucleotide mutation rate, population, and neutrality of mutations, show that the second specific mutation appears after 9 million years.”

De novo gene birth is the process where new genes arise from previously non-coding DNA sequences. These "newborn" genes can code for proteins or function as RNA genes. The exact mechanisms are unclear, but they may involve mutations that create open reading frames (ORFs) or transcriptional activation. This process contributes to genetic novelty and can play a role in and adaptation.

Here are 10 ways in which de novo gene birth by Neo-Darwinism is improbable:

  1. De novo gene birth requires a large number of mutations to occur in a specific order. This is because a new gene must be created from non-coding DNA, which is typically much longer than coding DNA. The mutations required to create a new gene must also occur in the correct order, otherwise the gene will not be functional.

  2. Many of the mutations required for de novo gene birth are likely to be harmful. This is because most mutations that occur in DNA are either neutral or harmful. Harmful mutations are more likely to be eliminated making it less likely that they will accumulate to create a new gene.

  3. De novo gene birth is a rare event. This is because it requires a large number of mutations to occur in a specific order, and many of these mutations are likely to be harmful.

  4. De novo gene birth is more likely to occur in populations with small effective population sizes. This is because populations with small effective population sizes are more likely to experience genetic drift, which can allow harmful mutations to accumulate. However, small populations are also more likely to go extinct, which would eliminate any new genes that are created.

  5. De novo gene birth is less likely to occur in complex organisms. This is because complex organisms have more genes, and each gene is likely to be more important for the organism's survival and reproduction. As a result, complex organisms are less likely to tolerate mutations that disrupt gene function.

  6. De novo gene birth is more likely to occur in non-coding DNA. This is because non-coding DNA is less likely to be under the pressure of natural selection. However, non-coding DNA also plays important roles in regulating gene expression, and mutations in non-coding DNA can have negative consequences for the organism.

  7. Many de novo genes are likely to be pseudogenes. Pseudogenes are genes that have lost their function due to mutations. Pseudogenes are more likely to be created than functional genes, because they require fewer mutations. However, pseudogenes are not beneficial to the organism, and they can even be harmful.

  8. De novo genes are likely to be expressed at low levels. This is because they are typically created from non-coding DNA, which is less likely to be transcribed into RNA. As a result, de novo genes are less likely to have a significant impact on the organism's phenotype.

  9. De novo genes are less likely to be inherited by offspring. This is because they are typically located in non-coding DNA, which is not always passed down to offspring. As a result, de novo genes are less likely to contribute to the evolution of the population.

  10. De novo genes are more likely to be lost over time. This is because they are typically expressed at low levels and are less likely to be inherited by offspring. As a result, de novo genes are more likely to disappear from the population over time.

In addition to these 10 points, it is important to note that Neo-Darwinism does not provide a satisfactory explanation for how de novo gene birth can lead to the creation of new and complex traits. For example, Neo-Darwinism cannot explain how the eye evolved, which is a complex organ that requires many different genes to function properly. Overall, the evidence suggests that de novo gene birth by Neo-Darwinism is a highly improbable event. It is more likely that new genes are created through other mechanisms, such as gene duplication and recombination.


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