Several years back I taught an undergraduate seminar course on society and genetic technologies. Our liveliest discussion topics were often centered on a technique used by in vitro fertilization docs to screen embryos for genetic errors, known as preimplantation genetic diagnosis, or PGD for short. The technique was created for one primary reason - to allow couples with a family history of life-threatening genetic disease the opportunity to conceive a healthy child. By using in vitro fertilization to create embryos outside of the womb, in a petri dish, scientists can pluck a single cell from each of the developing embryos and test that cell's DNA for errors. Some will carry the error, others not. Those free of the defect can be implanted back into the mother and allowed to develop, hopefully, into a healthy baby. An article in last week's Wall Street Journal suggests that PGD will increasingly be used by parents who wish to tailor their soon-to-be child's physical traits. Sex. Eye color. Complexion. "Athletic ability." The idea that many of these traits can be "ordered up" is just bunk. There is no genetic test for athletic ability or intelligence. Even eye and hair color, traits which we know are genetic, are complicated to predict. The high cost of IVF and genetic testing - upwards of $20,000 - will alone keep the number of "designer babies" low. One has to wonder, though, how many couples would take advantage of a cheap, easy way to choose the cosmetic traits or sex of their kids? What if the cost were $200? The $20,000 question: where does "reproductive freedom" end and a common moral standard begin?