| Genetic Testing in a Petri Dish Could Eliminate 'Imperfect' Humans--Before Implanting in Mom Genetic testing is changing modern medicine to detect, treat, and even prevent diseases, but one procedure allows scientists to test embryos developed in the laboratory so that only "healthy" embryos are implanted into the womb, experts said at the National Press Club on Tuesday. "Pre-implantation" screening is done by egg fertilization in a Petri dish and then the embryos are screened so that those with genetic disorders can be eliminated, said panelist Sherri Bale, a medical geneticist and co-founder of GeneDx, a company that offers molecular diagnoses of hereditary disorders. Bale explained the benefits of "pre-implantation" screening, in one scenario, by describing how genetic testing can be used for families that have a child who has the most common form of muscular dystrophy, which she described as a "constitutional" gene "mutation" that is present at the time of conception. "One in 3,500 males will have muscular dystrophy of this type," Bale said. "(It's) characterized by muscle weakness that starts very early in childhood, as early as age two, three, and most of these children are in a wheelchair by the time they are 12, unable to walk. And because it's a muscle disease that also affects the heart muscle that allows you to breathe . these children die, they are not children anymore, early in their 20s." Bale said another benefit is testing the child's sisters to see if they might be at risk for bearing a child with muscular dystrophy. "Or better yet, pre-implantation genetic diagnosis for that mom and what that means is we are going to make the diagnosis because we are going to get mom's egg and dad's sperm and we're going to put them in the Petri dish," Bale said. "We're going to test those embryos and we're going to find out which ones don't carry the mutation and those embryos can be implanted back into the mom and then she can have a baby that's virtually guaranteed not to have this disease." When asked by CNSNews.com whether genetic testing will allow parents to only have what they consider perfect children, panel members did not answer the question directly but instead praised the decision-making of patients and clients. "It's amazing to me that given good information how rarely people make decisions badly," Jamie McDonald, genetic counselor, told CNSNews.com. "I've had many families say that without the availability of the testing, they would not have had any more children," Bale said. "That would have been the end of their family. What we are able to do is allow them to continue to have children and build their families." The event, sponsored by the Results for Life, a clinical testing advocacy group, also highlighted how genetic testing is making possible a "personalized medicine approach" that is better at diagnosing and treating diseases, including cancer and heart disease. Members of the panel also advocated for the federal government, through the National Institutes of Health, to fund more research and development of genetic testing. Bale also spoke of laws in all 50 states that require screening newborns for as many as 20 genetic conditions, some of which can be treated if diagnosed at birth, including phenylketonuria or PKU. This condition is an enzyme deficiency that causes mental retardation, if untreated. "If PKU is not treated, these children become mentally retarded early on, they have seizures, they do not become a contributing member of society and they take a tremendous amount of care," Bale said. With treatment, she said, "they would become normal contributing members of society, and functional as long as they stay on their diet." Contact: Penny Starr Source: CNSNews Source URL: http://www.cnsnews.com Publish Date: October 29, 2008 Link to this article: |
October 29, 2008
Genetic Testing Could Eliminate 'Imperfect' Humans
