Genome Map Completed
An international consortium of scientists announced Monday that it has completed the map of the human genetic code to an accuracy of 99.99 percent and said the accomplishment opens a new era for biology and medicine.
The group announced in 2000 that it had completed a rough draft of the code, and the new report said the sequence is now "essentially complete" and freely available on computer databases to scientists all over the world.
Already, the group said, the computer databases carrying the sequences are getting more than 120,000 visits a day.
"After three billion years of evolution, we have before us the instruction set that carries each of us from one cell egg to adulthood to the grave," said Dr. Robert Waterston, of the International Human Genome Sequencing Consortium, an organization of 18 institutions that participated in the project.
Dr. Francis Collins, head of the National Human Genome Research Institute, the lead National Institutes of Health agency in the project, said the American share of the effort was completed ahead of schedule and under budget. The project started in 1990 and was expected to last 15 years at a cost of $3 billion. It was completed at a cost of $2.7 billion in less than 13 years.
He said the project is delivering, into public databases, "a remarkable gift to all of humankind — all of the letters to our human construction book."
Collins said the next step is to apply this new fundamental knowledge and he forecast revolutions in biology, medicine and in society.
Just when the predicted medical benefits will be harvested is still uncertain, Collins said, but he forecast that it will touch every phase of medicine and disease treatment in coming centuries.
The leaders of the six countries whose scientists participated in the effort issued a joint statement — released by the White House — welcoming the work as providing a "fundamental platform for understanding ourselves."
In addition to President Bush, the statement was signed by Jacques Chirac, president of France; British Prime Minister Tony Blair, German Chancellor Gerhard Schroeder, Japanese Prime Minister Junichiro Koizumi and Wen Jiabao, premier of China.
The genome is the collection of genes that form the DNA that contains the instructions for life. In humans, it's about 3.12 billion pairs of chemicals that form between 35,000 and 40,000 genes.
A gene is a group of those pairs, and each gene is a single instruction for the makeup of a being. Faulty genes can lead to various diseases; researchers hope that once they can read the entire code they can figure out where problems exist and, one day, correct them.
In the 2000 announcement, Collins said about 97 percent of the chemical pairs had been identified. He said researchers eventually hoped to sequence the genome to an accuracy of 99.9 percent. Because every human being has a unique genetic pattern, researchers are not expected to ever reach 100 percent.
It was just 50 years ago that Watson and collaborator Francis Crick, working at Cambridge University in England, were able to figure out the structure of DNA.
The DNA molecule resembles a twisted ladder. It is made up of just four chemicals, called bases, with each "rung" made from a pair of these bases. The bases provide the genetic code. Just as a four-letter alphabet could spell out words, the sequence of the four kinds of bases along the length of the DNA molecule spells out the information stored in genes.