Viruses manipulating our evolution

[genphis]

i was wondering if anybody had any thoughts about the symbiotic relationship between us and viruses, and whether the fact that we are vehicles for them motivate them to to change us and modify our evolution.

 

[nobahar]

There's a book called Virolution by Frank Ryan. I can't comment on the book, however; as I haven't read it.
Richard Dawkin's also briefly talks about Viruses in evolution. Either in The Selfish Gene or The Extended Phenotype, perhaps both, I can't remember.

 

[genphis]

thanks i will take a look at the books regards genphis

 

[bobze]

i was wondering if anybody had any thoughts about the symbiotic relationship between us and viruses, and whether the fact that we are vehicles for them motivate them to to change us and modify our evolution.

I don't know that I'd call it symbiotic, viruses use us as replicators, not much benefit from our standpoint.

Interestingly enough though, a significant portion of our genome is given over to endogenous retroviruses.

If you don't like sharing ancestors with apes, try on sharing them with non-living, infectious particles :P

 

[Ygggdrasil]

It is possible that we do derive some benefit from retroviruses, however. We know that retroviruses, either the infectious kinds of the kinds that have become endogenous mobile genetic elements, have the ability to reshuffle our genetic material. For example, a retrovirus can accidentally replace part of its sequence with DNA from the host. When this virus integrates into a new position in the genome, that host sequence will have moved to a new position in the genome where it can possibly adopt a new function.

While this process certainly can be harmful--for example, the idea of oncogenes, cancer causing genes, were first discovered when researchers realized that cancer-causing genes from a variety of tumor viruses were actually genes taken from the host's genome--it is possible that this process has also aided the host's evolution by generating more genetic diversity. For example, this process would promote recombination between different regions of the genome, allowing genes with new functions to arise. This could be one explanation for why endogenous retroviruses are so prevalent in our genomes.

 

[bobze]

It is possible that we do derive some benefit from retroviruses, however. We know that retroviruses, either the infectious kinds of the kinds that have become endogenous mobile genetic elements, have the ability to reshuffle our genetic material. For example, a retrovirus can accidentally replace part of its sequence with DNA from the host. When this virus integrates into a new position in the genome, that host sequence will have moved to a new position in the genome where it can possibly adopt a new function.

While this process certainly can be harmful--for example, the idea of oncogenes, cancer causing genes, were first discovered when researchers realized that cancer-causing genes from a variety of tumor viruses were actually genes taken from the host's genome--it is possible that this process has also aided the host's evolution by generating more genetic diversity. For example, this process would promote recombination between different regions of the genome, allowing genes with new functions to arise. This could be one explanation for why endogenous retroviruses are so prevalent in our genomes.

That's certainly true and I'd agree with all of it. My point wasn't that there isn't some specialized circumstances where we could consider viruses beneficial, my point was in general the relationships between viruses and humans is rather one sided.

 

[genphis]

another thought is where did they originate from, seeing as they need a host and most have difficulty in surviving outside living organisms for any length of time. what or who? was the original host , and are we just macro viruses ourselves. i ask this because if you look at our behavior patterns even the way we reproduce it seems pretty much like a virus type process any thoughts.

regards genphis

 

[Quantum-lept]

If a parasite can cause behavior change, then any pathogen has the possibility to do so.

""Epidemiological and neuropathological studies indicate that some cases of schizophrenia may be associated with environmental factors, such as exposure to the ubiquitous protozoan Toxoplasma gondii. ""
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1560245/

 

[cesiumfrog]

I'm reading Carl Zimmerman's "parasite rex". Aside from being quite readable and extremely interesting, it seems to give examples of how the role of parasites (if not viruses specifically) has been overlooked (in evolution, etc). (E.g., in particular environments >95% of fish the birds catch have parasites, which alter the fish behaviour to better facilitate transmission, and bringing into question the role the birds might play in that ecosystem otherwise.)

 

[Evo]

I'm reading Carl Zimmerman's "parasite rex". Aside from being quite readable and extremely interesting, it seems to give examples of how the role of parasites (if not viruses specifically) has been overlooked (in evolution, etc). (E.g., in particular environments >95% of fish the birds catch have parasites, which alter the fish behaviour to better facilitate transmission, and bringing into question the role the birds might play in that ecosystem otherwise.)

This is a subject I find quite interesting. It is amazing how dependant relationships have evolved to become so species specific in some cases that the loss of one means the extinction of the other.

The book sounds very interesting cesiumfrog, thanks!

 

[The riddler]

I remeaber reading a few years ago that a virus partially changed the DNA of the tuberculosis bacterium causing a new strain. I'm sure that at one time or another during our evolution from simple to complex orginisms that viruses had some sort of effect on our DNA like in the example above.