On Apr. 14, 2003, The International Human Genome Sequencing Consortium, led in the U.S. the National Human Genome Research Institute (NHGRI) and the Department of Energy (DOE), announced the successful completion of the Human Genome Project more than two years ahead of schedule. The international effort to sequence the 3 billion DNA letters in the human genome is considered by many to be one of the most ambitious scientific undertakings of all time, even compared to splitting the atom or going to the moon.

“The Human Genome Project has been an amazing adventure into ourselves, to understand our own DNA instruction book, the shared inheritance of all humankind,” said NHGRI Director Francis S. Collins, M.D., Ph.D., leader of the Human Genome Project since 1993. “All of the project’s goals have been completed successfully – well in advance of the original deadline and for a cost substantially less than the original estimates.”

The flagship effort of the Human Genome Project has been producing the reference sequence of the human genome. The international consortium announced the first draft of the human sequence in June 2000. Since then, researchers have worked tirelessly to convert the “draft” sequence into a “finished” sequence.

Finished sequence is a technical term meaning that the sequence is highly accurate (with fewer than one error per 10,000 letters) and highly contiguous (with the only remaining gaps corresponding to regions whose sequence cannot be reliably resolved with current technology). That standard was first achieved for a human chromosome when a team of British, Japanese and U.S. researchers produced a finished sequence for human chromosome 22 in 1999.

The finished sequence produced by the Human Genome Project covers about 99 percent of the human genome’s gene-containing regions, and it has been sequenced to an accuracy of 99.99 percent. In addition, to help researchers better understand the meaning of the human genetic instruction book, the project took on a wide range of other goals, from sequencing the genomes of model organisms to developing new technologies to study whole genomes. As of April 14, 2003, all of the Human Genome Project’s ambitious goals have been met or surpassed.