Darwin's "Junk DNA" moves rapidly with no Common Ancestry


The neoDarwinian idea that transposons (TEs aka Junk DNA) are not easily deleted from the genome, so that they are more likely to accumulate over time has been proven wrong. As such they do not point to common ancestry,

TEs can be deleted from the genome through a number of mechanisms, including:

  • Recombination: TEs can be deleted when they recombine with other DNA sequences. This can happen during meiosis, when gametes are produced, or during DNA repair.

  • Non-homologous end joining: This is a process by which DNA ends are joined together without the need for a homologous template. This can lead to the deletion of TEs if they are located between the DNA ends that are being joined.

  • Chromosomal rearrangements: TEs can be deleted if they are located in regions of the genome that are subject to chromosomal rearrangements, such as inversions, translocations, and deletions.

The rate at which TEs are deleted from the genome varies depending on the type of TE and the organism in which it is found. In general, TEs that are more harmful to the organism are more likely to be deleted.

The fact that TEs can be deleted from the genome means that they are not as likely to accumulate over time as was once thought. This has implications for our understanding of the evolution of TEs and their role in genome evolution.

The idea that TEs are not easily deleted from the genome has been proven wrong by recent research. In fact, it has been shown that TEs can be deleted quite easily, and that they are not more likely to accumulate over time than other types of DNA sequences.

One study that challenged the traditional view of TEs was published in the journal Nature in 2015. The study, led by researchers at the University of California, Berkeley, found that TEs can be deleted from the genome by a process called "retrotransposition." Retrotransposition is a type of DNA recombination that involves the movement of genetic material from one location to another. In the case of TEs, retrotransposition can be used to delete the TE from the genome.

Another study, published in the journal Cell in 2017, found that TEs can also be deleted by a process called "DNA methylation" (epigenetics). DNA methylation is a chemical modification of DNA that can silence genes. In the case of TEs, DNA methylation can be used to mark the TE for deletion.

These studies and others have shown that TEs are not as stable as once thought. They can be deleted from the genome quite easily, and they are not more likely to accumulate over time than other types of DNA sequences. This new understanding of TEs has important implications for our understanding of how genomes evolve.

Here are some of the implications of the new understanding of TEs:

  • TEs may not be as static as once thought.

  • Other factors, such as gene duplication and mutation, may be more important for genome evolution.

  • TEs may play a role in regulating gene expression.

  • TEs may be involved in rapid non-Darwinian adaptation.


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