Scientists say they've nearly finished deciphering the human genetic code.

It's what some are calling the "Book of Life." The announcement was made at the White House today.

NBC's Jim Hanchett explains what this advancement in science may mean for the future.

The scientists credited with completing a rough draft of the human genetic code get a triumphant White House welcome. The music, the applause, is followed by remarkable praise.

President Clinton: "Today we are learning the language in which God created life."

All possible, the president says, because what's called the Book of Life has virtually been decoded.

"With this profound new knowledge, human kind is on the verge of gaining immense new power to heal."

Here's how it happened. Scientists from a private company--Celera Genomics, in Maryland--have been competing with a group backed by the government.

Together, they've mapped the 50,000 or so genes that we inherit from our parents and that determine what we are. Why some people have black hair, or blue eyes.

But also why some people get diseases like cancer and why some don't. In the long run that could lead to better treatments, even cures.

Dr. Craig Venter, President and CEO, Celera Genomics Corp.: "There will be discoveries made across the board. But it's impossible to predict which diseases, at this point, will see the breakthroughs first."

But the scientists and the President do share a fear--that the genome discoveries will be used to discriminate.

Other critics of the research worry that somehow by knowing so well what we are, the mystery of life has been lost.

But the President says this advancement will have the opposite effect, giving us ever more awe for the complexity, the beauty that is human life.