A Health Spotlight on the human genome
Celera Genomics announces it reached the first step in mapping the human genome (4/6/00)
Should companies be able to use their findings on the human genome for profit? (3/16/00)
A discussion with Matt Ridley, author of Genome: The Autobiography Of A Species In 23 Chapters. (2/29/00)
Progress in deciphering the human genome (12/2/99)
Browse the NewsHour's coverage of Health
from the beginning:
Center for Biotechnology Information -- Human Genome Sequencing
Inside is Out
Scientists have revealed the map of the entire human genome. That's the genetic material contained in human cells that contains the "instructions" for creating a human being.
Robots break down molecules, scientists race to figure out the code that makes our bodies work, and companies spend millions of dollars researching high-tech medicines.
This isn't the plot of the latest sci-fi film; it's the very real story of the race to map the human genome.
After a decade of work and billions of dollars of research, an international team of scientists have finished sequencing the genetic information of the human body -- the formula for human life that is stored in tiny, complicated molecules of Deoxyribonucleic acid, commonly known as DNA.
So what's a nucleotide? It's a sub-unit of DNA made up of three components: an organic base, a phosphate molecule, and a sugar molecule (called deoxyribose).
These four are connected to each other in a "genetic code" sequence that researchers have just recently been able to decipher. The sequence of nucleotides within a nucleic acid may not seem to be in any order at first, but we know that it is this sequence that encodes the genetic information.
The order of bases (A, T, G, C) in your DNA will determine whether your eyes are blue or brown, or whether your hair is straight or curly.
Instructions for these traits are inherited from your parents, and "written down" in your DNA. But sometimes the instructions can get messed up, or copied wrong.
The result can be anything from a major birth defect to an increased likelihood for being overweight. Scientists hope that by cracking the code to these instructions they can help prevent and correct such problems.
Cracking the Code
Some people like to describe cracking the genome as plotting the map of a living organism. Others compare it to writing an encyclopedia that contains all the information about an organism, with each rung on the DNA strand acting like its own chapter.
The complete chemical code for each person's DNA is over 3 billion letters long. If scientists printed out a list of all the letters of the chemical code they would have a stack of paper higher than the 555-ft. Washington Monument!
Don't worry, you're not alone. Only a few years ago scientists thought the puzzle was so complicated they would never figure it out. It has only been with the help of new technology and powerful computers that they have been able to piece it together.
Race to the Finish
The race to crack the code has sparked one of the most heated scientific competitions in history.
The two major "code crackers" are Craig Venter, the president of the private company Celera, and Dr. Francis Collins, director of the National Human Genome Research Institute, a public health research facility funded mostly by the government.
Collins' Human Genome Project (HGP) has been plugging away at the genome since 1990. It originally planned to identify and sequence the code by 2005 but has recently announced it would finish the project sometime this month. New technology helped speed the project along.
Meanwhile, Craig Venter has been working on the exact same project for his private company.
Venter started out at the National Institute of Health (NIH) -- one of the backers of the Human Genome Project -- but became frustrated with their slow pace and decided to start his own team.
In 1998, he claimed that he could beat Collins and the NIH by using a riskier approach and by relying heavily on robots and computers to break down genetic material.
His gamble paid off and just over a year after he started, his company pulled ahead of the public genome project. Even Venter was a little surprised at his success. "We knew it would either work spectacularly or be the biggest flameout in history," he said.
Collins got angry. He criticized Venter for using the groundbreaking research to make a profit by selling it to pharmaceutical companies, and for using research produced by Collin's public research team. Unlike Celera, The Human Genome Project posts its findings for free on the Internet every 24 hours. Since Celera is a private company, it considers the information it discovers to be private property and can sell its findings for money.
Venter shot back, saying he would release all the results when they were complete and defended his right to sell information he discovered fair and square. He also pointed out that Collins' research was public property and he had as much right to it as anyone else.
Even though it may be driving each side to work faster, many outsiders are sick of the war of words between Collins and Venter and accuse both teams of cutting corners in order to win the race.
We don't know the half of it
Once scientists crack the code and map the human genome what are they going to do with it?
Each human being is 99.9 percent identical to every other human being, in terms of the chemicals that make up our bodies. But the 0.1 percent difference is incredibly important. These tiny variations can make people vulnerable to certain diseases and develop differently.
By finding out early if our genes put us at risk for certain problems, we can change our lifestyles to avoid them. Plus, scientists hope to one day use this research to manufacture drugs and manipulate genes, to prevent problems from arising.
The opportunities to save and improve human life are virtually endless. And we don't even know the half of it. Genome researchers remind us that we don't know how genes actually work and there is no telling what we can learn about ourselves from these studies.
But cracking the secrets of life also raises many important ethical questions. Some people think scientists shouldn't be "playing God" with other people's lives.
What would happen if parents could choose the sex, race and even the features of their unborn babies? And, more immediately, how will we live in a world where our DNA tells so much about us? Do we really want schools, insurance companies, employers, salesmen and the government reading our personal blueprints?
Should we even be fooling around with the basic secrets of life?
Some have predicted a world of genetic prejudice, where rich and powerful people can artificially alter their genes and those of their kids to remove all defects.
That means the rest of us with ordinary imperfect genes, could be considered inferior. Some people even imagine a time when an elite group could genetically engineer themselves and their children into a new "super-species" that would actually be genetically distinct from humans as we now know them.
President Clinton signed an executive order in February protecting federal employees from genetic discrimination in the workplace. That means you can't be refused a job because of anything that is found in your genetic makeup. And there are bills waiting in Congress intended to protect us in other parts of life.
But scientists assure us we have time to prepare. Even though Celera and the Human Genome Project have almost completed the mapping process, both models will need to be patched up and "spell checked" many times before they approach the goal of 99.9 percent accuracy.
In addition, a complete sequence of the genome doesn't tell us very much until we can actually read the code. In the long sentence of chemical letters it is difficult to determine where one gene ends and the other begins. Most of it is "junk DNA," genetic material that doesn't seem to play any role at all, and scientists will have to learn to distinguish between the two.
It could be years before the cracking of the genome affects our lives, but this month's announcements will certainly cause many to think about the changes to come.
What do you think? How will mapping the Human Genome affect our lives?
--contributed by David Berman
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