Genome map shows unclear patterns, many unknowns
By Robert Marmoz
LYON, France, Feb 9 (Reuters) - Carrying a potentially dangerous gene such as one for a type of cancer does not mean a person will necessarily come down with the disease, the head of the company that has mapped the human genome said on Friday.
Craig Venter, president and chief scientific officer of U.S. firm Celera Genomics Inc. (NYSE:CRA - news), told a medical conference in this eastern French city that the genome map showed human genes were highly similar to those of rats, dogs and mice. Scientists had not yet figured out the function of about 40 percent of them, said Venter, whose company plans to unveil on Monday the map of the human genome that researchers hope will help create new treatments for age-old diseases.
``There is no determinism in genes,'' Venter told the three-day conference on life sciences. ``Just because you have the gene for colon cancer doesn't mean you'll get colon cancer.''
Venter said outside factors such as proteins around the gene or influences from outside the body could influence a potentially dangerous gene, effectively turning it off so that it did not trigger disease.
Writing out the sequences of the A's, T's, C's and G's that make up DNA has confirmed that only tiny changes in this ``book of life'' can lead to quite different results.
``Mathematically, we are all virtually identical twins,'' he remarked. ``But we know that twins are always different.''
Setting down the location and sequence of the three billion letters that make up the human code still did not tell scientists which instructions each single gene gave the body.
``Forty percent of our genes have unknown functions,'' he said.
``UNLOCK MYSTERIES OF LIFE''
Celera, a commercial company based in Maryland, has teamed up with genome hunters at the U.S. Department of Energy and Compaq Computer (NYSE:CPQ - news) to write powerful computer programs and build a supercomputer to go through the genome sequence and find out where the genes are and what they do.
When Clinton administration officials announced this project last month, they said the scientists were ``writing the first draft of the future'' to ``unlock the mysteries of life''.
The human genome was sequenced late last year, but the sequence only gives the code for the human genetic map. Now the code has to be broken.
The A's, T's, C's and G's that make up DNA repeat over and over again in monotonous patterns that send important signals to our bodies but make our eyes glaze over wearily.
Computers can find the meaning in the patterns, even when they are only occasional minor changes in letters spread out over millions of genes.
Celera made its own sequence while the publicly funded Human Genome project, which includes the Energy Department, made another. Many genes are already known, but the code is so dense that it is not yet even clear how many genes there are.
Celera has a computer centre as big as a football field, Venter said, to crunch through the genetic information. |
