EMBRYO SCREENING: Sickle-Cell Anemia Test in Question
In a move some bioethicists are calling a wise use of technology, but has others calling for boundaries on genetic selection, scientists have for the first time genetically screened embryos for sickle cell anemia and used in vitro fertilization to successfully implant selected, disease-free embryos. The study, published in today's Journal of the American Medical Association, details research conducted at Weill Medical College of Cornell University in New York City in which Dr. Zev Rosenweks and his colleagues used pre-implementation genetic diagnosis (PGD) -- a technique already used successfully for Tay-Sachs and cystic fibrosis -- to screen and implant three healthy embryos from a couple who had previously aborted two fetuses after amniocentesis at 10-weeks revealed they had sickle-cell anemia (Xu et al., JAMA, 5/12 issue). "Up to now, couples who had affected fetuses could only deal with it by having an induced abortion," said Rosenweks ( AP/Baltimore Sun, 5/12). Noting that the new technology could virtually eliminate the risk of sickle cell anemia, Rosenweks portends a "brave new world" in which "it will be possible to virtually eliminate the genetic diseases that are so devastating they lead to death in early childhood" (Schulte, Philadelphia Inquirer, 5/12). For that reason, many experts are hailing the procedure. Stuart Newman of New York Medical College and a board member of the Council for Responsible Genetics, said the procedure "is acceptable because it doesn't involve abortion or genetic manipulation of the embryo," but rather a more precise version of amniocentesis. That sentiment was echoed by Linda Anderson, president of the Sickle Cell Disease Association of America. "Any time there is an opportunity to have these kinds of breakthroughs, particularly to help those of child-bearing age make informed decisions about childbirth, I think it is miraculous," she said (Maugh II, Los Angeles Times, 5/12). Arthur Caplan, director of the Center for Bioethics at the University of Pennsylvania, called the selection process "morally preferable" to testing during pregnancy and aborting affected fetuses.
Fearing 'A Brave New World'
The success of the procedure has rekindled the debate over PGD, as experts fear a situation where parents would be allowed to tailor their embryos' genetic composition. And with costs for screening and in vitro fertilization approaching $20,000 per case, "it isn't likely to be accessible for many parents whose prospective children would benefit" (Winslow, Wall Street Journal, 5/12). Dr. Oswaldo Castro, director of the Sickle Cell Disease Center at Howard University, said he opposes PGD in general because while some embryos are chosen, others are passed over. "I treat a lot of people with sickle cell," he said, noting that "it's difficult for me to put a judgement, 'Well this one should never have been born'" (AP/Baltimore Sun, 5/12). As the technology improves, ethicists are speculating as to which genetic traits will someday mark an embryo as a throwaway. "We're just finding the gene for obesity, for a predisposition for Alzheimer's, for breast cancer," warned George Annas of Boston University's health law department, adding, "The possibility of screening an embryo for a predisposition to have a disease it may or may not get I find horrendous. These techniques raise a major societal issue. What kind of people do we think we ought to be?" (Philadelphia Inquirer, 5/12).