Wasteful Garbage?
by GutsThe blogosphere last week was buzzing over a study that shows that most of the human genome may not be transcribed. Many have said that the rest of the genome is therefore "junk" or "wasteful garbage". I think this is only one explanation among many.
All that "junk" DNA may actually be a sea of potentiality when it comes to function. It appears to be very difficult to make proteins out of the blue from an evolutionary perspective. One recent study has shown that proteins diverge very slowly. On the other hand, it is probably a lot easier to make regulatory elements.
Although some parts of noncoding regions within our genome will eventually reveal no detectable biological function, a growing hypothesis speculates that much of an organism’s genetic complexity is due to elaborate transcriptional regulatory signals embedded in our noncoding DNA that determine when, where, and what amount of a gene transcript is expressed.
May 27th, 2010 at 9:02 am
If a large portion of the genome is not transcribed, then the functional possibilities for it are pretty limited. But that does not mean it is completely functionless: non-transcribed DNA could serve as a reservoir of material for new RNA transcripts (which could become regulatory elements)or even new genes if segments are cobbled together with initiation sequences via recombination. Such reservoirs might even have adaptive value from an evolvability standpoint.
Comment by KC — May 27, 2010 @ 9:02 am
May 27th, 2010 at 10:37 am
Of course they do.
Where do you think the resources for a targeted search would be?
Comment by ID guy — May 27, 2010 @ 10:37 am