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Author Topic: How many ERVs are in human DNA?  (Read 2002 times)

Offline Supercryptid

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How many ERVs are in human DNA?
« on: 04/01/2014 06:57:59 »
Endogenous retroviruses are the remnants of retroviral infections in the DNA of humans and other jawed vertebrates (I imagine they are present in invertebrates as well): Endogenous retrovirus

I came upon a strange inconsistency when researching this matter, however. Some sources say that humans have ~200,000 ERVs and fragments (such as this one: Evidence for the Evolutionary Model) while others say ~98,000 ERVs and fragments (such as this one: Long-term reinfection of the human genome by endogenous retroviruses). I have found both figures on several other websites. Can someone explain this to me? I was thinking that one possible explanation might be that we have 98,000 unique sequences and 200,000 total sequences (including copies of unique sequences).

Another question is, just how many ERV elements do humans and chimpanzees have in common? One of the links above, "Evidence for the Evolutionary Model", indicates it is in excess of 99.9%. However, I have no found this figure quoted in a peer-reviewed paper. Anyone have any thoughts on that?


 

Offline evan_au

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Re: How many ERVs are in human DNA?
« Reply #1 on: 05/01/2014 09:39:25 »
One effect that can make a 2:1 difference is that we have 2 copies of all our chromosomes (except the X & Y in males).

Depending on whether you count 1 copy or 2 copies of an ERV in a chromosome will make a 2:1 difference in the quantity of ERVs you estimate for the human genome.
 

Offline Supercryptid

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Re: How many ERVs are in human DNA?
« Reply #2 on: 06/01/2014 06:13:39 »
One effect that can make a 2:1 difference is that we have 2 copies of all our chromosomes (except the X & Y in males).

Depending on whether you count 1 copy or 2 copies of an ERV in a chromosome will make a 2:1 difference in the quantity of ERVs you estimate for the human genome.
I ended up thinking of that same thing today. Perhaps 200,000 is simply a rounding of 196,000.
 

Offline yellowcat

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Re: How many ERVs are in human DNA?
« Reply #3 on: 25/03/2014 21:31:34 »
The figure I have heard quoted is that about 8% of the human genome consists of sequences of retroviral origin.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1079666/ [nofollow]
 

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Re: How many ERVs are in human DNA?
« Reply #3 on: 25/03/2014 21:31:34 »

 

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