Scientists have for the first time revealed the human genome sequence with the discovery that the human genetic blueprint is only about twice the size of a fruit fly's.
The head of China's gene research team told China Daily Monday that the Human Genome Project (HGP) will publicize its version of the human genome in Nature, a well-known magazine based in London, on Thursday.
The HGP team is a consortium of academic centers, mostly from the United States and Britain but with members in France, Germany, China and Japan.
China has finished 1 percent of the finished sequenced map, according to Liu Qian, director and professor at the China National Center for Biotechnology Development.
He said the findings were the first complete look at a genetic document of extraordinary strangeness and complexity.
Scientists have found there are far fewer human genes than previously believed, probably a mere 30,000 or so - only a third more than those in the roundworm. They have found vast expanses of desert-like regions, where the human genome sequence contains relatively few or no protein-coding genes at all.
Roughly a quarter of the genome could be considered desert, with lengthy gene-free segments.
The findings also show that more than a third of the genome contains repetitive sequences, suggesting that this so-called "junk DNA" needs further study.
In addition, every human being on the planet shares 99.99 percent of the same genetic code with everyone else. Individual variations represent just 0.01 percent, or 1,250 different letters, of the entire sequence.
These genetic instructions are all contained within 46 large DNA-containing molecules called chromosomes - 23 from each parent.
Liu quoted genome scientists as saying that the completed human genome sequence is expected to spur on medical advances in diagnoses, pharmaceuticals that reflect individual genetic variations, and possibly gene therapies targeting segments of the code responsible for disease.
He said ongoing research would go much further.
"The next step is to research the functions of repetitive DNA, the regulation of gene expression, protein interactions, signaling, the effects of the environment and other mechanisms that could contribute to an organism's complexity.
(China Daily 02/13/2001)
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