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canopuss
2010-May-30, 12:24 PM
If DNA is changing over time, how effective is it in DNA profiling ?

http://www.wisegeek.com/can-your-dna-change-during-your-life.htm

John Jaksich
2010-Jun-06, 06:09 AM
The question IMHO--is harder (and more subtle) than can readily be answered in a few posts. If you can re-phrase your question---and be more to the point---?

But, I will try to answer it part-way . . . One latest finding is that retro-viruses have played a role in shaping the proverbial family tree of life on Earth. This stems from a finding (?) that we (humanity) have descended from lower life-forms and they are readily marked by "incursions" into the DNA and gene-pool by retro-viruses.

So in short, (in gross over-simplification) there is a common "kernel" for all of life on Earth and as a the result of ( complex and subtle) an interplay of environmental and evolutionary dichotomy life grew into what is currently seen....

Here is a Favored You-Tube Video (AAAS --supposedly endorsed it)--- (It comes from the Cassiopeia Project)---
:
http://www.youtube.com/watch?v=8ZvTmgCk1Lo

HenrikOlsen
2010-Jun-06, 07:48 AM
From the link:

By some of the code, it should be understood that DNA change is tiny and infinitesimal, governing very few expressions of certain genes. Most of your building block DNA does not undergo change, and is not likely to.
The answer is that it's very effective, since the vast majority doesn't change.

G O R T
2010-Jun-06, 10:42 AM
If DNA is changing over time, how effective is it in DNA profiling ?

http://www.wisegeek.com/can-your-dna-change-during-your-life.htm

DNA profiling ? Criminal forensics?

99% of human DNA is the same in every human. Forensic analysis is limited to areas that differ. If the mutation was in that 99%, it will not be found.
Although we can have many mutations in our lifetimes, they are limited to the replacement cells of the effetced cell. Mutations do not spread.
Only mutations in the early tissues of the fetus can change the DNA in any significant portion of the body as they grow and diversify.

John Jaksich
2010-Jun-06, 10:45 AM
Agreed, HenrikOlsen

If the descent of humanity is agreed to be the sum of many different changes upon the DNA ---it would take many generations until our current, modern appearance could be discerned from an ancestor--whose appearance might bear more of a resemblance to one of the great apes who could not walk up-right as opposed to Homo erectus, for instance. Let the following diagram indicate the complexity:




Although the percent difference in the gene pool might be meagre (let's say .01 ---> .9 percent---if that much) the "visual" appearance might be striking . . .