The sequence of the human genome has been completed.

While the finality of such news is much more detailed than a single sentence allows, the International Human Genome Sequencing Consortium reported more in depth at a suburban Washington meeting that it had successfully completed the Human Genome Project more than two years ahead of schedule.

The finished sequence covers about 99 percent of the human genome's gene-containing regions, and it has been sequenced to an accuracy of 99.99 percent. The National Human Genome Research Institute (NHGRI) and the Department of Energy, both of which led the U.S. effort in the six-nation consortium, sponsored the two-day scientific symposium titled "From Double Helix to Human Sequence - and Beyond," in Bethesda, Md.

The announcement marked the end of the project that began in 1990.

In seeking an understanding of the role of genetics in human health and disease, the Human Genome Project's finished sequence represents a significant advance over the working draft first reported in June 2000. It covered 90 percent of the gene-containing part of the sequence, 28 percent of which had reached finished form, and contained about 150,000 gaps. The finished version contains 99 percent of the gene-containing sequence, with the missing parts essentially contained in less than 400 defined gaps.

Celera Genomics, a Rockville, Md., company, announced its draft of the genome at the same time in 1990 as the public group.

In addition, to help researchers better understand the genome's meaning, the public project took on a wide range of other goals, from sequencing the genomes of model organisms to developing new technologies to study whole genomes. Such accomplishments include an advanced draft of the mouse genome sequence, published in December 2002; an initial draft of the rat genome sequence, produced in November 2002; the identification of more than 3 million single nucleotide polymorphisms (SNPs); and the generation of full-length complementary DNAs for more than 70 percent of known human and mouse genes.

The consortium included hundreds of scientists at 20 sequencing centers in China, France, Germany, Great Britain, Japan and the U.S. The five institutions that generated the most sequence included Baylor College of Medicine in Houston; Washington University School of Medicine in St. Louis; the Whitehead Institute/MIT Center for Genome Research in Cambridge, Mass.; the Department of Energy's Joint Genome Institute in Walnut Creek, Calif.; and The Wellcome Trust Sanger Institute near Cambridge, England.

The NHGRI, a unit of the National Institutes of Health in Bethesda, said it would publish its vision for the future of genome research in the April 24, 2003, issue of Nature, coinciding with the 50th anniversary of its publication of the paper by Nobel Laureates James Watson and Francis Crick that described DNA's double helix. Watson also was the first leader of the Human Genome Project.