Private firm completes major step in human gene mapping

WASHINGTON - A private company mapping the human genetic blueprint said Thursday it has completed a major step: Decoding all of the DNA pieces that make up the genetic pattern of a single human being.

The milestone puts the company, Celera Genomics of Rockville, Md., far ahead of an international government effort to map the human genome using a different method.

''We've now completed the gene sequence plan of one human being,'' said Craig Venter, chief scientist for the company. He said that human being was an unidentified male, adding, ''By the end of next week, we will have finished the gene sequence for a female.''

There are about 3 billion DNA subunits in virtually every human cell. This DNA contains about 100,000 genes. The gene sequencing done thus far lines up small segments of the DNA. Assembly of the entire genome will involve putting these segments in proper order.

This process, said Venter, will take several weeks. But he said the Celera work is far ahead of a similar effort by the government-funded Human Genome Project.

''We don't want to declare absolutevictory yet, but call me in three or four weeks when it is all assembled,'' said Venter.

Dr. Francis Collins, the Human Genome Project's chief, said, ''I'm happy to hear that Celera has completed this part of their business plan. We look forward to hearing how the assembly process goes and ultimately seeing the sequence made available'' to the public.

Venter said the ordered sequence of the human genes will not be released to the public until it has been completely assembled.

''I don't believe a genome is done until there is an attempt to identify the genes and the linear sequence along all of the chromosomes,'' he said. ''We will not have that completed until later this year.''

The announcement by Celera drew a quick response from Wall Street investors. Shares of PE Corp., Celera's parent company, rose 26 points to 139 by midafternoon.

President Clinton's press secretary, Joe Lockhart, said the Celera announcement ''marks a ... significant point in what the president has talked about extensively as ... one of the most important scientific developments of our time.''

The Human Genome Project is expected to complete a ''rough draft'' of the human gene sequence this spring, but this will not be assembled into a finished order for several more years.

The federal project is using a different method than that used by Celera, which is using a technique developed by Venter.

But, in contrast to Celera, the federal project is releasing to the public the genetic sequences as they are identified. The federal project thus far as put on the Internet the codes for about 2.3 billion subunits of the DNA.

Clinton recently announced that the United States and Britain have agreed to share data from their efforts to decode the human genetic pattern. A U.S.-British statement urged private companies to follow the lead of government laboratories in sharing data. Some companies have shared data, while others have not.

In testimony before Congress, Venter said Thursday that his company will make the entire genome available on the Internet, but will provide special services for analyzing the massive amount of data to drug companies and to universities for a subscription price. Subscriptions for drug companies, he said, will cost millions, while the rate for universities will be in the thousands of dollars and not much more than what is now paid for some advanced software.

To decode the genetic sequence, Venter said his company drew specimens from 30 different people. One specimen was then used to draw up the completed sequence. A male was chosen because only males have at least one copy of all the chromosomes, including the X and Y sex chromosomes. Females have two Xs and no Ys.

''That one individual probably doesn't know who was selected for sequencing, but probably knows about being a donor in the pool,'' said Venter. ''All 6 billion of us on this planet differ enough from each other so that no one individual is significant. It is significant only as a reference source and because it is the first one.''

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