Better "hearing" by "Junk DNA" without Darwin


The paper "Accelerated Evolution Analysis Uncovers PKNOX2 as a Key Transcription Factor in the Mammalian Cochlea" by Maglia et al. (2022) investigated the role of the transcription factor PKNOX2 in the evolution of high-frequency hearing in mammals.

The authors first used accelerated evolution analysis to identify noncoding DNA elements (NCEs) (aka junk DNA) that had undergone rapid evolution in inner ear transcription factor genes. They found that PKNOX2 harbored the largest number of NCEs within its transcriptional unit.

To further investigate the role of PKNOX2 in high-frequency hearing, the authors generated Pknox2-deficient mice using CRISPR/Cas9 technology. They found that Pknox2-deficient mice had reduced distortion product otoacoustic emissions (DPOAEs) and auditory brainstem response (ABR) thresholds at high frequencies, suggesting that PKNOX2 is essential for cochlear sensitivity at higher frequencies.

A comparative cochlear transcriptomic analysis of Pknox2-deficient and wild-type mice revealed that key auditory genes are under PKNOX2 control. This suggests that PKNOX2 plays a critical role in the regulation of cochlear sensitivity at higher frequencies.

The authors' findings provide new insights into the evolution of high-frequency hearing in mammals by NonDarwinian Junk DNA. They suggest that PKNOX2 played a key role in the evolution of this trait.

Noncoding DNA is outside of NeoDarwinism because it does not directly encode proteins. However, noncoding DNA can still play an important role in gene regulation. For example, NCEs can act as enhancers or silencers, which can influence the expression of nearby genes.

The findings of the Maglia et al. (2022) study suggest that noncoding DNA may play an even more important role in evolution than previously thought. By influencing the expression of genes, NonDarwinian noncoding DNA can indirectly affect the evolution of traits. This is an area of active research, and it is likely that we will learn more about the role of noncoding DNA in evolution in the years to come.

NonDarwinian Noncoding DNA can affect phenotypic plasticity and adaptation. Phenotypic plasticity is the ability of an organism to change its phenotype in response to environmental changes. This can be a very important adaptation, as it allows organisms to survive and reproduce in a variety of environments.

Noncoding DNA plays a role in phenotypic plasticity by regulating gene expression. Genes are turned on and off by proteins called transcription factors. These transcription factors bind to specific sequences of DNA, called regulatory elements. Noncoding DNA can contain regulatory elements that control the expression of genes.

When environmental conditions change, the expression of genes can also change. This is because the binding of transcription factors to regulatory elements can be affected by environmental factors. For example, the binding of transcription factors to regulatory elements can be affected by temperature, pH, or the availability of nutrients.

Changes in the expression of genes can lead to changes in the phenotype of an organism. For example, if the expression of a gene that controls the production of a protein that helps an organism to survive in cold temperatures is increased, the organism may be able to survive in colder temperatures.

In addition to regulating gene expression, noncoding DNA can also affect phenotypic plasticity by affecting the structure and function of chromatin. Chromatin is the complex of DNA and proteins that makes up chromosomes. The structure of chromatin can affect the accessibility of DNA to transcription factors. This, in turn, can affect the expression of genes.

Therefore, noncoding DNA plays an important role in phenotypic plasticity and adaptation outside of NeoDarwinism. By regulating gene expression and the structure of chromatin, noncoding DNA can help organisms to respond to environmental changes and survive in a variety of environments.

Here are some examples of how noncoding DNA can affect phenotypic plasticity and adaptation without neo darwinism random mutations:

  • In plants, noncoding DNA can affect the expression of genes that control the production of proteins that help plants to respond to changes in light, temperature, and water availability.

  • In animals, noncoding DNA can affect the expression of genes that control the production of proteins that help animals to respond to changes in temperature, diet, and stress.

  • In humans, noncoding DNA has been linked to a variety of traits that are affected by environmental factors, such as height, skin color, and susceptibility to diseases.

The study of noncoding DNA and its role in phenotypic plasticity and adaptation is a rapidly growing field of research. As we learn more about noncoding DNA, we will gain a better understanding of how organisms are able to adapt to their environment outside of NeoDarwinism.

The study compared the Junk DNA between mice and humans among other mammals.

Mice and humans share about 80% of their exons, which are the protein-coding regions of DNA. It only makes up 2% of the total DNA. However, the noncoding DNA and epigenetic factors in mice are different from those in humans, which leads to different phenotypes (bodies).

Noncoding DNA is the vast majority of DNA in the genome (98%), and it does not directly code for proteins. However, it can play a role in regulating gene expression, which can affect the phenotype. 


Percentage of human exonic DNA (only 2% of DNA) versus epigenetic phenotype determination using the 98% Junk DNA.

Epigenetic factors are chemical modifications to DNA that can also affect gene expression.

The different noncoding DNA and epigenetic factors in mice and humans can lead to different phenotypes in a number of ways. For example, a gene that is expressed in mice but not in humans may be responsible for a trait that is unique to mice. Or, a gene that is expressed in both mice and humans may be regulated differently in the two species, leading to different levels of gene expression and different phenotypes.

The study of how noncoding DNA and epigenetic factors contribute to phenotypic differences between mice and humans is an active area of research. This research has the potential to shed light on the genetic basis of human diseases, and to develop new treatments for these diseases.

Here are some examples of how noncoding DNA and epigenetics can affect phenotypes:

  • In mice, a gene called Agouti is involved in regulating coat color. The Agouti gene has two different alleles, one that is expressed in mice and one that is not. Mice that have the Agouti allele that is expressed have a black and white coat, while mice that do not have the Agouti allele have a yellow coat.

  • In humans, a gene called BRCA1 is involved in repairing DNA damage. Mutations in the BRCA1 gene can increase the risk of developing breast cancer. The BRCA1 gene is regulated by epigenetic factors, and these factors can influence the risk of developing breast cancer.

These are just a few examples of how noncoding DNA and epigenetics can affect phenotypes. This is a complex and rapidly evolving field of research, and there is still much that we do not know about how these factors contribute to phenotypic differences between individuals and species.


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