DNA chart ahead of schedule

A "working draft" of the human genetic blueprint will be translated and on paper well ahead of schedule and probably within a year, according to the head of the US National Human Genome Re search Institute.

Researchers around the world are working to produce the "book of life", the letter-by-letter sequence of the estimated three billion building blocks of human DNA. This would provide a map of the 80,000 human genes which dictate the colour of our hair and skin, our height and susceptibility to diseases.

The US Genome Project to sequence the human genome began in 1990 and was due for completion by 2005, but things were moving faster than expected, according to Dr Francis Collins, who heads the institute.

"Originally researchers thought they would not start cataloguing human variation until 2005, but now they expect to have an excellent catalogue completed by 2001," he told an American Medical Association conference on genetics yesterday in San Francisco.

The gene discoveries will help uncover many of the major hereditary factors for virtually every disease of a hereditary nature and will reveal the causes of complex and common diseases such as multiple sclerosis, common cancers, hypertension and schizophrenia, he said.

Once the sequence is established and the variability catalogued - thought to amount to only 0.1 per cent of the total genome - researchers will try to figure out how it all works. "It's like building the periodic table for chemistry. We will have built the periodic table for human biology, but then we'll have to figure out how these genes all interact with each other in health and disease," he said.

A key ethical and scientific issue will be whether all of these data remain freely accessible to researchers and the public.