University researchers and other members of the International Human Genome Consortium announced the successful completion of the Human Genome Project more than two years ahead of schedule at an April 14 news conference in Washington, D.C.
By completing the Human Genome Project, researchers believe they are launching a new age of discovery that will transform human health.
Knowing the order of the genetic building blocks — commonly abbreviated A, T, C and G (adenine, thymine, cytosine and guanine) — should allow scientists to learn more about human development and disorders such as heart disease, psychiatric illness and cancer.
Already the genome sequencing effort has helped spur discoveries about breast cancer, colon cancer, prostate cancer, cystic fibrosis, Huntington's disease, Parkinson's disease and sickle cell disease.
The project, completed 50 years after James Watson and Francis Crick discovered the structure of DNA, succeeded in sequencing all of the DNA in human chromosomes. The sequence of more than 3 billion genetic "letters" carries the instructions for making and operating the human body and the errors or variations in the genome that contribute to most types of disease.
In the future, many believe patients will receive prescribed medical treatment based on their genes rather than on their age or weight. In addition to such individualized treatment, researchers hope genome-based research will enable medical science to develop highly effective diagnostic tools and a better understanding of how a person's individual genetic makeup influences health or susceptibility to disease.
"The completed genome sequence is an extremely powerful database for the study of human biology," said Richard K. Wilson, Ph.D., professor of genetics and of molecular microbiology and director of the Genome Sequencing Center. "Because of limitations in technology, there are still small gaps in the sequence, but if you compare it to a 5,000-page book, it's as if a few words are missing on a couple of pages. Those missing words, however, are not at critical points in the story, so this 'finished' sequence should tell us the story we need to know."
With the sequence complete, Wilson said the challenge for researchers and scientists is now to learn how to read the pages of this "book of life" in order to understand how all the various parts work together.
Wilson and his colleagues at the University said the next steps will involve closely searching the more than 3 billion pieces of information in the human genome for clues about human disease and comparing genetic information about humans with information gathered from mapping and sequencing the genomes of other species.
Last year, the mouse genome was mapped and sequenced. The Genome Sequencing Center is working on the chimpanzee and chicken sequences. In addition, the bacterium Salmonella typhimuriam and the plant Arabidopsis thaliana have been mapped and sequenced.
"By sequencing all of these genomes, we will identify genes that do certain jobs in particular animals, and by looking for similar DNA patterns among various species, we hope to isolate crucial genes that play key roles in making us sick or keeping us healthy," Wilson said.
The project's information has been free and publicly available on the Internet since the Human Genome Project was launched by its researchers in 1988.