Is The End Of Disease In Sight?

It appears unraveling the secrets of the entire human genetic code was the easy part. Now scientists say successfully applying the "book of life" to the benefit of mankind - curing diseases, pinpointing which genes do what and perfecting gene splicing - is still years down the genomic road.

With Monday's announcement that the entire human genetic code has been assembled, researchers now have a thrilling to-do list for the 21st century.

The information could be used to cure cancer, Alzheimer's disease or diabetes. It could give patients valuable information about their susceptibility to heart disease, schizophrenia or high blood pressure. It could reveal in detail how an adult human being arises from a single cell, functions through a lifetime and dies.

But it could take decades before such dreams become reality.

"I would guess, seven to eight years you and I - if we're interested - will find out what particular conditions we're at risk for," Francis Collins, of the Human Genome Project, said Tuesday on CBS News' The Early Show. "Give us another 10 years and the drugs that we currently use will be replaced by those that are targeted on a genomic view."

President Clinton joined a government project and private venture Monday in announcing the virtual completion of the first rough map of the human genetic code, an achievement the president called "a day for the ages."

The public effort headed by Collins has mapped 97 percent of the human genome and thoroughly covered, or sequenced, 85 percent. The for-profit rival, Celera Genomics of Rockville, Md., also announced Monday that it has completed 99 percent of the genetic sequence.

Celera began its work last fall, using an approach that turned out to be faster than conventional methods.

"I spent 10 years trying to find one gene. Francis has spent 10 years trying to find one gene. That 10 years I took with all my colleagues and hundreds of millions of dollars of government funding is now a 15-second computer search on the computer," Celera chief scientist and president Craig Venter said. "That's a new start.

Scientists involved in both projects intend to publish their results jointly later this year. They will also convene a meeting to share what they do know about how the genes work.

The goal of both teams is to identify and place into proper order the 3.12 billion chemical base pairs present in human DNA and to identify within that DNA the thousands of human genes. The base pairs are made up of four types of nucleotides, called adenine, thymine, cytosine and guanine. They are abbreviated A, T, C and G in the scientific description of the genome.

It is the order and sequence of these bases within the 23 pairs of human chromosomes that make up the genetic code.

In the near term, the new information is expected to revolutionize drug development, making it much easier for pharmaceutical companies to target their products at the actual causes of disease. Today, most drugs are developed by a trial-and-error method that simply throws thousands of compounds at a biochemical problem until one fixes it.

"If you think of any disease that comes to mind - except maybe trauma - every disease has some hereditary component," Collins said. "We have a chance to go to the basic molecular causes and develop therapies much more precisely targeted to what's wrong and tailor them."

Researchers are also pursuing gene therapy, which would replace or supplement defective genes with correct copies. But researchers have found it difficult to find an efficient way to deliver corrected genes to cells where they are needed; they remain optimistic that effective methods will be found.

Book of life? Is a new supergeneration in our future?