Posts Tagged ‘Junk genes’

Junkies versus Non-junkies: Junk genes are not junk — or maybe they are

February 24, 2013

Myopic “scientists” bitching about each other is always interesting. Scientific theories have their own evolutionary life as some wither and die and some – gradually – become accepted and “proven”.  But it is the behaviour of the protagonists of rival theories which is entirely human. Rivalry, back-biting and childish insults in the world of evolutionary biology between junk-gene supporters and junk-gene debunkers are now getting entertaining.

Animation of the structure of a section of DNA...

from wikipedia

In September last year the ENCODE Project made a major splash when they published some 30 papers in front-line journals showing that most of the human genome dismissed earlier as as “junk genes”  did in fact show biological activity and probably had some as yet unknown function. They reported that they had transcribed some 76% of “junk” DNA and that more than 50% of all genes could be accessible to proteins which can control genetic behaviour and they concluded that over 80% of human DNA serves some purpose.

The term “non-coding” DNA, then popularised as”junk” genes, was coined in 1972. This idea  gradually gained favour and by 2003 the human genome was supposed to consist of some  26,000 protein-coding genes within a large amount of non-coding DNA where the non-coding or “junk” DNA represented some 98% of the whole genome. The results of the ENCODE project turned this idea on its head. The junk gene supporters were not amused. It has taken them a little while to circle the wagons and formulate a response to the flood of papers published in September. And the response resorts to unusually harsh language for scientific discourse. It would seem that the “junk” gene protagonists have been prodded in their vitals and feel their life-work and their livelihoods being threatened!

Junkies versus Non-junkies! The battle-lines have been drawn. They have now published an open-access diatribe: On the immortality of television sets: “function” in the human genome according to the evolution-free gospel of ENCODE

The Guardian: “Everything that Encode claims is wrong. Their statistics are horrible, for a start,” the lead author of the paper, Professor Dan Graur, of Houston University, Texas, told the Observer. “This is not the work of scientists. This is the work of a group of badly trained technicians.”

Scientists are being called technicians — no less!

The junkies write:

From an evolutionary viewpoint, a function can be assigned to a DNA sequence if and only if it is possible to destroy it. All functional entities in the universe can be rendered nonfunctional by the ravages of time, entropy, mutation, and what have you. Unless a genomic functionality is actively protected by selection, it will accumulate deleterious mutations and will cease to be functional. The absurd alternative, which unfortunately was adopted by ENCODE, is to assume that no deleterious mutations can ever occur in the regions they have deemed to be functional. Such an assumption is akin to claiming that a television set left on and unattended will still be in working condition after a million years because no natural events, such as rust, erosion, static electricity, and earthquakes can affect it. The convoluted rationale for the decision to discard evolutionary conservation and constraint as the arbiters of functionality put forward by a lead ENCODE author (Stamatoyannopoulos 2012) is groundless and self-serving.

Would the Junkies  – I wonder – allow 98% of their DNA – or that of their children – to be excised if it could be?

Advertisements

%d bloggers like this: