Posted on 01/31/2010 9:08:09 AM PST by EnderWiggins
Endogenous retroviruses are the remnant DNA of a past viral infection. Retroviruses (like the AIDS virus or HTLV1, which causes a form of leukemia) make a copy of their own viral DNA and insert it into their host's DNA. This is how they take over the cellular machinery of a cell and use it to manufacture new copies of the virus.
Sometimes, the cell that gets infected by such a virus is an immature egg cell in the ovary of a female animal. Such cells can be stored in a state of suspended animation or dormancy for as much as 50 years before they complete meiosis and become mature egg cells ready to be fertilized. Because they are dormant gene expression is suppressed and the infection cannot take over the cell and kill it. If that egg later matures and is fertilized, the newborn organism will have that endogenous retrovirus in every one of its cells, and so will all of its descendants.
Every viral infection is unique. The complete genome of an animal is so huge, and the insertion point of a viruss DNA is so random that it is statistically impossible for any two individuals to have the same exact endogenous retrovirus in the same exact spot on the genome unless they both inherited it from a common ancestor who had the original infection. And the infection of a germ cell is so rare that ERVs make up only somewhere between 1% and 8% of the entire human genome.
If two humans have the same identical ERV, it is proof that they are descended from a common ancestor. And if two different species have the identical ERV, it is proof that they too are descended from a common ancestor. In humans, there are about 30,000 different ERVS embedded in each person's DNA. Except for those later duplicated by a duplication mutation, all of them record unique infections of a single ancestral individual. Now here is where it gets really interesting.
There are at least seven different known instances of shared ERVs between chimps and humans... i.e. ERVs which are the identical viral DNA inserted into the identical spot of the genome. 100% of all chimps and 100% of all humans have these same ERVs. This is only possible if 100% of all chimps and all humans are descended from the single individual that had these original infections.
They are proof that humans and chimps share a common ancestor.
In a 2000 paper published in the journal Gene researchers identified ERVS shared by different primates and used them to assemble a family tree of monkeys apes and humans. Yes... we share ERVs with these lower primates as well. Here is what it looked like:
Figure 4.4.1. Human endogenous retrovirus K (HERV-K) insertions
in identical chromosomal locations in various primates
(Reprinted from Lebedev et al. 2000)
The arrows show the relative insertion times of the viral DNA into the host genome (determined using the genetic clock of accumulated later point mutations). All branches to the right carry that ERV - a reflection of the fact that once a retrovirus has inserted into the germ-line DNA of a given organism, it will be inherited by all descendants of that organism.
Reference: Lebedev, Y. B., Belonovitch, O. S., Zybrova, N. V, Khil, P. P., Kurdyukov, S. G., Vinogradova, T. V., Hunsmann, G., and Sverdlov, E. D. (2000) "Differences in HERV-K LTR insertions in orthologous loci of humans and great apes." Gene 247: 265-277.
That’s entirely silly. The promoter region is the start of the genetic processing engine itself!
Do you have a software background at all? Serious question (and yes, I realize that you are going to puff puff back questions about my own background with biology simply because you are so far gone).
Nope. You have to have the centromeres for cell division. It's part of the signaling command coding structure. The telomere protects against genetic data deterioration via redunduncy, but it's STILL GENETIC CODE!
I guess your statement that “all DNA has the genetic code” was your idiotic way of claiming that all DNA is functional.
Now you are insisting that all functionality is some sort of “code” and that is a misuse of the word, as well as being rather idiotic. Must I ask you again if you consider a philips head screwdriver fitting into a philips head screw as some sort of “code”?
A centromere is not part of the genetic code, but it does have functionality. All functionality is not a code, and only if it is translatable into an amino acid sequence is it the GENETIC code.
Short repeat DNA has no known function, and it is also not part of the genetic code. And again I repeat to you, because you seem to be having a real hard time figuring it out, functionality does not imply a “code”.
Where do you dream up such nonsense?!
A short tandem repeat (STR) in DNA occurs when a pattern of two or more nucleotides are repeated and the repeated sequences of genetic data are directly adjacent to each other (in intron sections of DNA data).
That's still genetic data!
Incorrect. Not all genes in DNA code for amino acid proteins. Other sections of DNA data are transcribed to precursor mRNA.
That's *STILL* genetic code being processed and used in DNA.
That's entirely incorrect and betrays a fundamental lack of knowledge of DNA (e.g. transcribing into mRNA).
Wow are you TRYING to be obtuse, or are you just so ignorant that you cannot help it?
How many times must I mention to you that DNA is transcribed into mRNA and that it is the mRNA that is translated via the GENETIC CODE into the amino acid sequence of a protein before you realize what it is I am talking about.
DNA to mRNA isn’t a “code” in the same way that mRNA to an Amino Acid sequence is a code. The only code to transcribe DNA into mRNA is that A = A, C = C, G = G, and T = U. That is not the genetic code.
Moreover, not all DNA is transcribed into mRNA. Thus this does nothing to back up your idiotic assertion that all DNA contains the genetic code.
Please tell me what functions short repeat DNA has been shown to have. You insist that it has a function, what is it?
Do you consider a philips head screwdriver fitting into a philips head screw to be the enactment of some sort of “code”?
If you do it would go a long way towards explaining your delusion that anything having to do with DNA must be some sort of code (even if it is not specifically the genetic code).
The genetic code is something specific. Not all DNA contains information translatable via the genetic code any more than every string of letters and numbers conveys an intelligible message when fed into an enigma machine. The promoter region of a gene is no more in genetic code than the introduction to a coded message is part of the code.
“Ok, we have a special message for all our little orphan Annie fan club members.” is NOT in code, not part of the code, and doesn’t contain code.
The alphanumerics that needed to be deciphered into BESURETODRINKYOUROVALTINE was what was in code, the code key being the little decoder ring.
The “decoder ring” for the genetic code is that chart I posted. Unless the DNA sequence can be transcribed into mRNA that is translated into a functional amino acid sequence via the “decoder” of a ribosome; it simply cannot be said to contain the genetic code.
Unless of course you want to sound like a complete ignoramus.
Oh good grief. Your posts get more ridiculus with each attempt. Short repeat DNA is just an observed *pattern* in existing DNA. Sheesh.
Contrary to your machinations, all DNA is code or data. Some of the code is digital (base 4). Other parts of the code are analog (e.g. signaling inputs for replication).
Honestly, you’ve gone too far with your denials and blather. Your mind is made up regardless of facts presented, though no doubt you’ll continue to deny that axiom, too.
Only a small percent of the genome is actually made up of DNA that is part of the genetic code or regulatory sequences that control the transcription of that code.
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