Want a daughter with blond hair, green eyes and pale skin?

A Los Angeles clinic says it will soon help couples select both gender and physical traits in a baby when they undergo a form of fertility treatment. The clinic, Fertility Institutes, says it has received "half a dozen" requests for the service, which is based on a procedure called pre-implantation genetic diagnosis, or PGD.

While PGD has long been used for the medical purpose of averting life-threatening diseases in children, the science behind it has quietly progressed to the point that it could potentially be used to create designer babies. It isn't clear that Fertility Institutes can yet deliver on its claims of trait selection. But the growth of PGD, unfettered by any state or federal regulations in the U.S., has accelerated genetic knowledge swiftly enough that pre-selecting cosmetic traits in a baby is no longer the stuff of science fiction.

But Fertility Institutes disagrees. "This is cosmetic medicine," says Jeff Steinberg, director of the clinic that is advertising gender and physical trait selection on its Web site. "Others are frightened by the criticism but we have no problems with it."

PGD is a technique whereby a three-day-old embryo, consisting of about six cells, is tested in a lab to see if it carries a particular genetic disease. Embryos free of that disease are implanted in the mother's womb. Introduced in the 1990s, it has allowed thousands of parents to avoid passing on deadly disorders to their children.

In a recent U.S. survey of 999 people who sought genetic counseling, a majority said they supported prenatal genetic tests for the elimination of certain serious diseases. The survey found that 56 percent supported using them to counter blindness and 75 percent for mental retardation.

More provocatively, about 10 percent of respondents said they would want genetic testing for athletic ability, while another 10 percent voted for improved height. Nearly 13 percent backed the approach to select for superior intelligence, according to the survey conducted by researchers at the New York University School of Medicine.

Embryo screening, for example, is sometimes used to create a genetically matched "savior sibling" — a younger sister or brother whose healthy cells can be harvested to treat an older sibling with a serious illness.

Trait selection in babies "is a service," says Dr. Steinberg. "We intend to offer it soon."

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