Mysterious DNA withstand Eons of Evolution

Mysterious Snippets Of DNA Withstand Eons Of Evolution

Small stretches of seemingly useless DNA harbor a big secret, say researchers at the Stanford University School of Medicine. There's one problem: We don't know what it is. Although individual laboratory animals appear to live happily when these genetic ciphers are deleted, these snippets have been highly conserved throughout evolution.

I found this article very interesting. People have been aware of these large sections of "junk" DNA in our genome, and recently the scientist who made the above discovery also found that they did express proteins.

The really interesting part is how these sections are conserved for such long periods of time.

It's not that these regions are somehow protected against change: they are mutated in about one in 200 healthy humans. Rather, these changes seem to be swept away over time by the tides of evolution in a process called "purifying selection." Bejerano and McLean believe that something similar may be happening in the laboratory mice on a scale too subtle to be seen under carefully controlled experimental conditions.

"Interestingly," said Bejerano, "the longer the sequence has been in us, the less likely it is to be lost. It's almost like the bricks in the foundation of a building, which hold up the rest of the structure."

It makes you wonder if the human genome is following a predefined path.

Isn't there a theory floating around that junk DNA is actually comprised of bits of virus DNA that's been inserted over the ages?

Very interesting that they are so heavily conserved, even though -- by all appearances, anyway -- they serve no purpose.

I am really out of my 'zone' on stuff like this...

...but could it be that it never had reason to mutate because it is worthless, and not in spite of it?

If it serves no purpose, then perhaps it is simply staying the same because the process only 'selects' that which is beneficial to changing circumstance.

Like I said, I am way out of my zone here and am probably missing some basic understanding to how and why DNA changes over time.

I think I heard a theory about how humans a long long time ago used this DNA, but then somehow something made it inactive. And there is a way that you can "activate" it again. I don't know if it is true, but it is possible.

its not so much 'junk' DNA, more of 'blank' DNA,
It needs to be there to allow for evolution,
There is only so many ways to evolve with 'base' DNA,
To allow for greater ways of evolution there needs to be 'spare' code

i think its the programing left over from fertilization that told the dna what its building bone \ organ \ skin etc ...