MYSTERIOUS DNA

'Junk DNA' throws up precious secret

A collection of mystery DNA segments, which seem to be critical for the survival of many animals, are causing great interest among scientists.
Researchers inspecting the genetic code of rats, mice and humans were surprised to find they shared many identical chunks of apparently 'junk' DNA.
According to the traditional viewpoint, the really crucial things were genes, which code for proteins - the "building blocks of life". A few other sections that regulate gene function were also considered useful. The rest was thought to be excess baggage - or 'junk' DNA.
But the new findings suggest this interpretation was somewhat wanting.
Scientists have just found 480 streches of at least 200 base pairs of DNA in humans, mice, rats, chickens, dogs and fish are identical.
The really interesting thing is that many of these "ultra-conserved" regions do not appear to code for protein. If it was not for the fact that they popped up in so many different species, they might have been dismissed as useless "padding". "These initial findings tell us quite a lot of the genome was doing something important other than coding for proteins," researcher Professor Haussler of UCA said.

[Professor Chris Ponting, from the UK Medical Research Council's Functional Genetics Unit, told BBC News Online: "Amazingly, there were calls from some sections to only map the bits of genome that coded for protein - mapping the rest was thought to be a waste of time.
He added: "I think other bits of 'junk' DNA will turn out not to be junk. I think this is the tip of the iceberg, and that there will be many more similar findings.]