The original Question was:
All apes, including humans, share some Endogenous Retrovirus (ERVs) in common that do not exist in any other mammals. So if you find a dog with an ape ERV you could falsify evolution. Have they found contradicting ERVs to this yet? Or is there some reason why they likely won’t find?
Answer by Diane Eager
First of all: what are Endogenous Retroviruses?
Retroviruses are viruses that not only infect cells, but incorporate their genes into the genome of the host cells. They are called retroviruses because they carry their genetic information in the form of RNA. When they infect a cell the RNA information is transcribed onto DNA and the DNA is then inserted into the genome of the cell. The “retro” in the name refers to the fact that the transfer of genetic information from RNA to DNA is the reverse of what normally happens in cells. The norm is that genetic information is stored on DNA then transferred onto RNA, which is then used the make proteins in the cell.
The most well-known retrovirus is the Human Immunodeficiency Virus (HIV) which causes AIDS. Other retroviruses cause immune deficiency diseases in animals, and cancers in both humans and animals.
Endogenous means originating or growing within a living organism. A retrovirus is said to become endogenous when it is incorporated into germline (eggs or sperm) and is passed onto the next generation. From then on the viral DNA is within the genome of the organism, and will continue to be passed on to successive generations. The sequence of DNA that originally came from the virus is now called an Endogenous Retrovirus or ERV. Because these supposedly came from a random infection, they were considered to be genetic parasites and part of what has been labelled “Junk DNA”.
This process is believed to have happened in the past in human and animal evolution because sequences of DNA that are similar to the viral genetic information have been found in human and animal DNA. If similar stretches of viral DNA are found in two species that is regarded as evidence they both evolved from a common ancestor, who was originally infected with the virus.
A second question: Are these evidence for evolution?
Any transfer of DNA from a retrovirus into a germline to form stable genes that can be inherited has never actually been observed. Infections with retroviruses normally target non-germline tissue, e.g. white blood cells, and result in life threatening diseases like AIDS, leukaemia or cancer. Therefore, any claim about ERVs as evidence for evolution is believed by faith, and not based on observation.
A Third question: Is finding the same DNA sequence in apes and people evidence for evolution?
No. It simply indicates that both of these species need that same stretch of DNA. This has been affirmed by recent research that showed DNA sequences believed to be ERVs actually have useful functions, e.g. in the development of the placenta in mammals, including humans.
This also means that finding the same DNA sequence in apes and dogs would neither falsify nor confirm evolution. It would simply indicate that both apes and dogs need that DNA information to function.
We predict that further research will find functions for other DNA sequences previously written off as ERVs or as Junk DNA in general. For more of Junk DNA see the Creation Research Fact File. Insert “Junk DNA” in the search box.
Image: HIV viruses being shed by a lymphocyte, Public Domain
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