Imagine if you could choose your baby the same way you pick out a new outfit from a catalogue. Perhaps some blue eyes, a bit of curly hair, and why not make her tall, lean and smart? One fertility doctor now says that he may be able to deliver.
Dr. Jeffrey Steinberg has already helped thousands of couples choose their child's gender at his fertility institutes in Manhattan and Los Angeles. Within six months, he says, the clinic will offer a new service: allowing couples to select the physical traits of their babies. Steinberg says he cannot promise that people will get their selections, but claims he can dramatically increase the probability.
"I can't say with 100 percent certainty that parents will be able to choose something like eye color -- more like 80 percent certainty," Steinberg said.
The procedure is called pre-implantation genetic diagnosis, or PGD. It's been used by fertility doctors for years to screen embryos in the lab -- mostly for parents who want to reduce the chances of carrying a baby with life-threatening diseases.
According to Steinberg, the technology behind genetic screening has progressed to the point where parents can almost custom-design their babies.
It isn't clear that Steinberg can safely deliver on his claims. ABC News spoke to a variety of geneticists and fertility experts who disagreed about whether this science is actually possible. Many said it seemed conceivable. Others were not so sure.
"Theoretically, I suppose, as our ability to probe the human genome, and to apply various tests to a specific gene that has been discovered," said Dr. Zev Rosenwaks of New York-Presbyterian Hospital/Weill Cornell Medical Center. "That possibly anything can be looked for and potentially identified and applied."
But Rosenwaks said he strongly opposes the possibility, adding that is not the role of a physician.
Science's understanding of genes is way ahead of the ethical debate surrounding designer babies. While there is no legal prohibition against customizing your baby's traits, the reality of a brave new reproductive world generates enormous emotion.
"There is no more important question that is going to face us than deciding how to control and use genetic engineering and genetic selection to design our kids. Nothing," said Art Caplan, ethicist at the University of Pennsylvania.
"Designing your descendents and seeking out perfection is the biggest slippery slope we could go on," he said. "Are the rich going to be able to do it and the poor not? Are we going to create a sort of subpopulation of the genetically perfect as against everybody else?"
Are parents playing God? Couples routinely choose the sex of their new baby and are able to carefully screen egg and sperm donors, but many say this advancement takes it too far.
Steinberg says that designing your baby is on the verge of becoming reality. The question for parents, doctors, and society is whether this is progress and if they are on board.