Less than 10% of human DNA has functional role, claim scientists

[natasa778]

http://www.theguardian.com/science/...uman-dna-functional-genome-biological-baggage

...
More than 90% of human DNA is doing nothing very useful, and large stretches may be no more than biological baggage that has built up over years of evolution, Oxford researchers claim.

The scientists arrived at the figure after comparing the human genome with the genetic makeup of other mammals, ranging from dogs and mice to rhinos and horses.

...

Gerton Lunter, a senior scientist on the team, said that based on the comparisons, 8.2% of human DNA was "functional", meaning that it played an important enough role to be conserved by evolution.

"Scientifically speaking, we have no evidence that 92% of our genome is contributing to our biology at all," Lunter told the Guardian.

...

But other scientists take a broader view of what it means for DNA to be functional. Most of the 92% that Lunter's group says is not functional DNA is still active in some way in the body.

"Many [DNA] elements that play important roles in human disease are not evolutionarily conserved. Some of these have human-specific functions, some are involved in late-onset diseases like Alzheimer's, and others are simply missed by current comparative genomics methods," said Manolis Kellis, a computational biologist at MIT who was not involved in the study. "We cannot simply ignore the remaining 90% of the genome that is not evolutionarily conserved."

"Evolution can tell you whether something is important or not important, but it doesn't tell you what that something actually does," he added.

 

[natasa778]

followed by some very good comments by readers

 

[anciendaze]

I'm going to contribute my two cents worth before I check those comments. (This gives me a great chance to make a fool of myself.)

Some 8% of the human genome consists of HERVs and there is a great deal of argument about HERV activity. All I want to say here is that the claim made above puts the entire active part of human genomes on the same scale as sequences clearly inserted by retroviruses. Which organism is really in charge?

 

[A.B.]

Famous last words.

 

[taniaaust1]

Those scientists should experiment on themselves and remove 90% of their own DNA if it was possible and then share if it matters or not. I'd almost bet they wouldnt be functional anymore.

 

[alex3619]

This is a highly controversial claim. I am not sure how accurate it is. The argument is along the same line as the psychogenic inference. We don't know what it does, so it does nothing. We are learning that more and more of our DNA has roles other than the central dogma of biology has been saying. This includes control and regulatory functions that have nothing to do with making proteins.

I have no idea how much of the genome has biological relevance. I do know that we discover more and more of it is important as time goes on.

It is however not a bad argument that if areas of the genome are not conserved at all, then they have probably not had a strong evolutionary impact - yet.

Over time more and more of the genome will be assigned a function. Genomics is still in its infancy.

I may say more later after I have had some sleep.

 

[garcia]

Arghhh I hate the way the orthodox scientific establishment thinks. If they haven't found a use for it, it must be useless right? (because they are oh so smart and know everything). Remember when Glial cells (which outnumber neurons 10 to 1 in the brain) were thought to be just "glue", again because they didn't know what they did. I'd like a scientist to actually stand up and admit they don't know anything about anything, so journalists can stop making interpolations based on how little scientists know.

Any scientists reading this should write out 1000 times:
"Absence of Proof is not Proof of Absence"