2018/03/07

One genotype can produce a diversity of phenotypes - Epigenetics

One genotype can produce a diversity of phenotypes - DNA doesn't determine traits

https://blogs.scientificamerican.com/dog-spies/the-hidden-dogs-of-dog-cloning/?utm_source=twitter&utm_medium=social&utm_campaign=sa-editorial-social&utm_content=link-post&utm_term=biology_blog_text_free&sf183794341=1

Excerpt: "Dog cloners, and increasingly the general public, understand that clones are not always physical matches of the original. One genotype can produce a diversity of phenotypes, the outward physical appearance. After all, the first cloned cat named Carbon Copy (CC) looked nothing like the original, highlighted veterinarian Sophia Yin in an interview with geneticist Leslie Lyons: “The cool thing about CC is that it shows that even though two animals are genetically identical, they may not look or act identical. A clone is never actually identical because there are so many different environmental factors that come into play.”
 
And perhaps of most importance to pet owners, pet cloning companies increasingly admit that clones do not match the original pet’s personality. “The new puppies and kittens will be the same sex as the donor, but just as it is in nature, may have slight phenotypic differences 
(My comment: Sometimes the differences can be significant), such as different markings due to natural epigenetic factors,” reports Viagen Pets FAQ. “The environment does interact with genetics to impact many traits such as personality and behavior.”"

My comment: These two cats are genetically identical but they have different epigenomes. DNA genes don't determine traits of organisms. Please remember that the DNA is the same in every stage of metamorphosis of butterflies, for example.
 
The DNA is just passive information library that cells use for building RNA products. Epigenome means different types of epigenetic information layers and regulatory factors needed for cellular differentiation. These are DNA methylation, histone epigenetic markers, non-coding RNA molecules, regulatory proteins and over 140 different types of epigenetic markers of RNA. Organisms experience variation and adaptation due to changed diet types, climate, stress factors, sensory stimuli etc. Adaptation never leads to evolution because alterations in epigenetic information layers result in gradual but inevitable degradation or recombination of existing biological information. This can be observed as genetic mutations, loss of genes and chromosomes and negative consequences within organisms, such as pathogenic bacteria and viruses, parasites etc. The theory of evolution is the most serious heresy of our time.