The sci-fi fantasy of designing perfect babies has come a giant step closer to reality with the stunning announcement that researchers have decoded the DNA of an animal for the first time.
Now that researchers have mapped out all 19,909 genes of a microscopic roundworm, understanding the human genetic blueprint won't be far behind.
Scientists may soon be engineering babies - creating brilliant, disease-free superkids or even babies who could grow wings or have Einstein for a dad.
Research is pushing baby-making into a brave new world where parents could pick little Timmy's eye color, wipe out a family history of heart disease and boost his intelligence level - all before he's born.
''It fundamentally alters the parent-child bond for the first time in history,'' says Jeremy Rifkin, author of ''The Biotech Century.''
''The child becomes the ultimate shopping experience.''
Dad a little dull? Swipe the DNA of Babe Ruth or Jimi Hendrix and morph it into sperm for an instant celebrity papa.
Two legs not enough? Add a few more for extra traction.
Those are the most alarmist bio-future scenarios, triggering B-movie visions of mutant soldier-kids with wings and fangs or genetically enhanced super-beings who rule over unfortunate schlumps conceived the old-fashioned way.
For now, it's all just conjecture.
Scientists don't have the knowledge or technology to chisel children out of genetic marble - and ethicists are still debating whether they should be able to do it.
But consider where we are today:
* Doctors can test fetuses for chromosonal and genetic warps that cause about 1,000 of the 7,000 known genetic diseases like Down syndrome, Tay-Sachs disease and sickle cell anemia.
* The $3 billion federal Human Genome Project expects to map out the estimated 80,000 genes in the human body by 2003. A private firm, Maryland-based Celera, could do it sooner.
* An Israeli couple recently fertilized several eggs in vitro and then had the wife implanted with a girl because a male child had a high chance of having a life-threatening disease.
* Within a few years, a professor at the University of Southern California plans to experiment with gene therapy on embryos - trying to battle genetic disease by injecting the embryos with unmutated genes.
'Gene therapy for improving people is coming, and it will make it possible
to improve your eyesight, your sex life, your hairline and your disposition,''
said Glenn McGee, professor of bioethics at the
University of Pennsylvania and author of ''The Perfect Baby.''
How far away is a designer baby? Estimates run the gamut from 15 years to two centuries - to never.
The scientific gaps are still enormous. Doctors can test fetuses for diseases, but they can't cure them. Gene therapy on children and adults for the most part has been a disappointing failure.
And for all their progress, researchers don't have a handle on how genes really work. It's one thing to map out genes, but it's another to decode their soupy language.
Genes, holed up in the 23 pairs of chromosomes that humans acquire at conception, are tricky little protein-builders that mutate, switch on and off and seem to change functions.
Without knowing exactly how the puzzle fits together, fiddling with genes could lead to DNA disaster.
For example, if the technology were ready, parents understandably might be eager to somehow ''fix'' a mutated gene to prevent sickle cell anemia in their soon-to-be-newborn.
But scientists know the same mutation protects other people from malaria - and no one's quite sure if eliminating it would wreak havoc in the human gene pool.
''There is no such thing as a perfect child,'' said Dr. Victor Penchaszadeh, chief of medical genetics at Beth Israel Medical Center. ''Perfection is found in variety.''
Of course, biodiversity is all well and good until it's your kid who gets sick, he conceded. The link between sickle cell and malaria is just one example of the complexity in the human molecular blueprint - there could be thousands or millions of others.
Intelligence could be linked to a predisposition to heart disease; a sense of humor might be tied to nearsightedness.
''How do you know you're not doing more harm than good when you're messing around with genes?'' said Dr. Ruth Macklin, professor of bioethics at Albert Einstein College of Medicine. ''When do we know enough to start?''
Most ethicists assume science will figure out how to isolate gene function and develop the technology to banish bad traits and insert good ones.
That still leaves the big question: Is fooling with Mother Nature morally right? Many ethicists and religious leaders see a difference between ''fixing'' mutated genes to stop a disease and pulling a genetic switcheroo to have a child with red hair, green eyes and a knack for long division.
Rifkin, whose book predicts an age in which genes drive the world's commercial and social engines, does not see much of a line between the two. ''What we're actually talking about - and no one even wants to raise this - is eugenics,'' Rifkin said. It doesn't take a lot of imagination to see a world in which wealthy parents buy technology for brainy, athletic, charming progeny who don't get colic or colon cancer, Rifkin said.
He believes a new prejudice - DNA discrimination - will crop up against people whose parents didn't engineer them into perfection. Employers and insurance companies will shun the disabled, the fat, the weak, stutterers and everyone who falls short of the ideal.
McGee, who supports using genetic technology to cure disease, scoffs at visions of an Aldous Huxley world in which ''little munchkins are made in embryo factories.''
''I just can't imagine in the future reproduction will be that impersonal,'' he said. But we are creeping toward a dangerous mind-set regarding the definition of a ''normal'' person, he said.
People already hold parents responsible for what happens to children before they are born - wagging their fingers at wine-sipping pregnant moms and prosecuting pregnant drug users.
Ethicists wonder how long will it be before society - or even kids -
blame moms and dads for not fixing cleft palates or club feet at conception.
''Enhancements take our minds off the really important stuff
and allow us to obsess almost limitlessly about our most superficial
traits,'' McGee said.
Science and parents already go beyond nature to give kids a leg up in social competition - like manufacturing human growth hormone for super-short children or pushing a mildly talented clarinet player into three hours of lessons a day, Macklin said.
Why would changing the nose-shape gene in the womb be any different from breaking Sally's nose and resetting it when she turns 16?
''People have a freaky fear of genes and they say we have to draw the line somewhere,'' Macklin said. The government is still wrestling over where - or whether - to draw that line.
The National Institutes of Health will not fund any research that intentionally
changes a fetus' so-called germline cells that carry the genetic code from
generation to generation. But its policy is silent
about research that messes with those building blocks unintentionally,
as a side effect of work on other genes.
After a University of Southern California researcher told the NIH he planned to try gene therapy on fetuses that could affect the germline, protests poured into the agency. But no decision has been made on whether he'll be given a green light.
Macklin, who ponders the moral issues as a member of the NIH's Recombinant DNA Advisory Committee, said it will take time before a policy is developed, especially as the technology changes.
But there's another fundamental question lurking beneath the whole choose-your-own-baby concept - the age-old nature vs. nurture argument about what makes a person unique.
Will a jacked-up intelligence gene land Johnny in Harvard's Class of 2205 if he never picks up a book? Will extra serotonin guarantee a happy life for Susie if she has a terrible childhood? Maybe not. Many diseases can't just be snipped away. Only 5 to 10 percent of all cancers seem to have genetic links, so finding the culprit in the womb doesn't help much if the perfect baby grows up to be a smoking, drinking, red-meat-eating adult.
''I believe as much in environmental effects as I do in genes,'' Penchaszadeh said. Deciding a child should be a brown-eyed, curly-haired basketball player before she is born ruins the ''mysterious magical surprise'' of having a baby, McGee said.
''We hope we'll have a kid who becomes a ballerina but we're thrilled when this same kid goes out and does something we never thought of,'' he said. ''That's where you get the most growth for parents and children - and that's what you lose'' with designer babies.
dan@southeast.net
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