EXTRACTS: Professor Steve Jones, of University College London, describes the seismic implications of the new findings: "I once wrote a book called The Language of the Genes, but now biologists are beginning to face up to the uncomfortable truth that they have only been looking at the nouns in life's lexicon - the crudest and most basic elements of any tongue."
The new work identifies many more kinds of genetic punctuation that control how genes are read, amounting to 35 per cent more than previously recognised. No wonder, given our poor understanding of these control mechanisms, splicing new DNA into the genome by gene therapy has proved so difficult.
GM WATCH comment: To quote Richard Lewontin, professor of genetics at Harvard University, on genetic engineering: "We have such a miserably poor understanding of how the organism develops from its DNA that I would be surprised if we don't get one rude shock after another."
Life just got a lot more complicated
The Daily Telegraph, 19/06/2007
[note; there's also a video you can access at this link]
The deeper scientists look into the human genetic code, the more baffling it becomes but it is also increasing their understanding of disease, reports Roger Highfield
[image caption: Human code: scientists have found that so-called junk DNA is, in fact, important]
Seven years ago, with much ballyhoo, scientists unveiled the book of life - the DNA required to build and run a human being.
Last week, a small army of geneticists reported the results of the first systematic attempt to make sense of this book.
What they found makes uncomfortable reading for those who thought they understood the basics of biology, but it does provide tantalising hints of new ways to fight disease.
This, the most detailed study of DNA, is a landmark in genetics research, for the more scientists understand the details of how our bodies work, the easier it will be to fix them when they go wrong.
But the latest findings turn basic biology concepts upside-down, could rewrite conventional wisdom when it comes to common ailments, and contain many puzzles, including one that may even challenge our understanding of the way evolution works.
The basics of genetics go like this: DNA, or deoxyribonucleic acid, is a long chemical that is coiled up in sausage-like bundles, called chromosomes.
Two metres of DNA are crammed this way into the chromosomes within a single cell.
DNA is a ladder-like molecule twisted into a double helix, where the rungs consist of chemical units, called nucleotides.
These units are drawn from an alphabet of life that consists of only four letters - A, T, C and G (see graphic) - so the code reads GGGAAACCC and so on for around three billion letters, the entire complement, or genome, of one set of chromosomes.
This one-dimensional script, which was first revealed in 2000, "somehow carries within it all of the instructions necessary to take a single-cell embryo and turn it into a very complex biological entity called a human being," said Francis Collins, whose US National Human Genome Research Institute provided much of the funding for the new study.
But each cell uses only a small part of the genome, so that a cell from the liver, for example, would use a different part of the script to one from the brain.
To do this, cells contain molecular machinery that carries out the instructions held in particular genes, converting them into a second kind of genetic material, called RNA, which is in charge of the manufacture of the necessary range of proteins to build and operate each cell type.
A decade ago, most scientists speculated that because humans are so complex, it would probably take 100,000 genes to describe the awesome workings of an entire body, perhaps as many as 300,000. Then, seven years ago, when Francis Collins and Craig Venter unveiled a rough draft of the human genome in the White House, acres of newsprint remarked on how the actual number was closer to 25,000 genes - the same parts list as that of "simpler" creatures such as the sea urchin.
This entire complement of human genes, it was believed, resided in only around 1.5 per cent of the cell's DNA, prompting some scientists so dismiss vast swaths - the other 98.5 per cent - as "junk".
Now the most exhaustive probing of the genome to date, a GBP20 million pilot project, suggests the meaning of DNA's message remains elusive. Professor Steve Jones, of University College London, describes the seismic implications of the new findings: "I once wrote a book called The Language of the Genes, but now biologists are beginning to face up to the uncomfortable truth that they have only been looking at the nouns in life's lexicon - the crudest and most basic elements of any tongue.
Now we are reading the spaces in between - verbs, adverbs, adjectives, pronouns and all the rest, and they are complicated indeed. Worse, the genome babbles, stutters and mangles its pronunciation and now and again seems to speak utter nonsense."
The new understanding has come from an exhaustive analysis of one per cent of the genome, some 30 million letters of DNA, published in the journal Nature by an international team called the ENCyclopedia of DNA Elements (Encode) Consortium, along with 28 companion papers published in the journal Genome Research.
In all, this army draws on expertise from 35 groups in 80 organisations from around the world.
The analysis was led by Dr Ewan Birney, a computer scientist at the European Bioinformatics Institute, near Cambridge, who said the work "poses some interesting mechanistic questions". In layman's language, this is an admission that boffins are baffled.
Indeed, Dr Birney said scientists might even have to revise what they mean by the term "gene". "It is really challenging our dogmas," he said.
The most striking finding is
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