Brave New Baby Making

How an HB couple sidestepped Huntington’s disease Genetic screening to weed out embryos that harbor abnormalities can help parents protect their children’s futures. But critics contend the procedure serves as selective breeding. View PDF By BLYTHE BERNHARD The Orange County Register Like all new parents, Stacy and Mitch Brookhyser wonder who their baby girls will grow up to be. Where will they go to school? What jobs will they choose? Who will they marry? But there’s one question they don’t have to ask – whether the girls inherited a defective gene from their mother. The Brookhysers went through in-vitro fertilization and genetic screening of their embryos to ensure their twins, Roxanne and Laurel, now 9 months old, would not develop Huntington’s disease. “We cared about our kids before we ever had them,” said Stacy Brookhyser. “Doing this doesn’t mean our children are perfect. It just means this is one less thing to worry about.” Hundreds of babies have been born across the country through pre-implantation genetic diagnosis – selecting certain embryos over others to weed out genetic abnormalities from muscular dystrophy to hemophilia. For a fatal disease like Huntington’s, eliminating affected embryos is currently the only hope for a “cure.” Stacy Brookhyser, like her mother, aunt and grandmother, has a gene aberration that always leads to Huntington’s disease. If a cure is not found, the 31-year-old will probably develop symptoms in her late 50s or early 60s. The devastating illness affects almost every aspect of brain function, causing its sufferers to eventually lose mobility and cognitive skills. If conceived naturally, the Brookhysers’ children would have a 50 percent chance of inheriting the defective gene and therefore the disease. While it’s possible to test a fetus during pregnancy and then decide on an abortion, the Brookhysers wanted to test the embryos before Stacy became pregnant. The technology gave them some control over the insidious disease, she said. “I truly believe that God gave us this technology to be able to protect our next generation.” First, the couple had to prepare for in-vitro fertilization, in which a woman’s ovaries are stimulated with drugs to release extra eggs. The eggs are collected surgically and fertilized with sperm in the lab. When the embryos grow to eight cells a few days later, one cell is removed and tested for the malformed gene. Three of the Brookhysers’ nine embryos tested negative and were implanted in Stacy’s uterus. The cost of the procedure is prohibitive for many families. Embryo testing costs about $5,000, on top of $10,000 to $15,000 for the in-vitro fertilization treatments. The Brookhysers, who live in Huntington Beach, have health insurance through Mitch’s job with the Los Angeles County Fire Department. The insurance plan reimbursed 70 percent of one round of the screening and fertilization, which resulted in the birth of the twins. ETHICAL DEBATE Embryo selection has also been used to prevent the births of children with Down syndrome, cystic fibrosis and Tay-Sachs disease, among about 200 other conditions that are linked to a particular gene or chromosome abnormality. Some disability advocates say the screening is a form of discrimination and implies that a life with a disability or illness is not worth living. Groups against abortion are opposed to the procedure because it involves the destruction of embryos. “The basic objection is the clearest objection: it destroys human beings,” said Stephen Napier, a staff ethicist for the National Catholic Bioethics Center in Philadelphia. Other critics fear that embryo screening is a form of eugenics (selective breeding) and a steppingstone to choosing only those babies who will grow up athletic, beautiful and smart. Scientists say those fears are premature, since characteristics like height and intelligence are controlled by many genetic and environmental factors that can’t be controlled in a laboratory. Nevertheless, some European countries have banned certain types of embryo screening on moral grounds. In the U.S., there are no restrictions on how the technology can be used. One local ethicist said that’s a good thing. “It’s a technology that should be available to parents to utilize as they see fit for their family formation,” said Judith Daar, a professor at Whittier Law School in Costa Mesa who also serves on UC Irvine’s medical ethics committee. Others are opposed to the screening for less deadly or late-onset diseases. For example, someone who carries a gene that puts them at high risk for breast cancer won’t necessarily get the disease. And if they do, it could be 50 years down the line, after unknown advancements in treatment. Dr. Lawrence Werlin, the Brookhysers’ specialist at Coastal Fertility Medical Center in Irvine, said he favors national guidelines for reproductive technology. “You have to be careful. Are you eliminating an embryo that could have had a good future?” OTHER IMPLICATIONS While screening for specific genetic defects is the main reason the technique was invented, there are other, more controversial uses. Several fertility clinics in Orange County offer embryo screening to choose the sex of the baby. According to a Johns Hopkins University study, most Americans approve of embryo testing for medical purposes. A minority felt the same way about using it for gender selection. Sperm sorting is a less costly – and less controversial – method of gender selection because it doesn’t involve the elimination of embryos. But it’s also less reliable. Embryo screening is virtually perfect in predicting gender. It’s not always about balancing the family or preferring one sex. Some parents decide to choose the sex of their baby because they are worried about passing on a disease that primarily strikes boys or girls. Many fertility clinics offer embryo screening on demand to any couple undergoing in-vitro fertilization. After screening for chromosomal abnormalities that can lead to miscarriage, only the healthiest embryos are chosen to be implanted. Lately, the use of embryo screening as an infertility treatment has come under scrutiny by researchers, with some experts saying the technique is oversold by fertility clinics. Embryo screening prior to implantation resulted in a lower birth rate, when compared to in-vitro fertilization alone, in a large Dutch study published this month in the New England Journal of Medicine. Because fertility clinics are largely unregulated in the U.S., it is unclear exactly how many children have developed from embryos that have been screened for any reason. For the Brookhysers, the costs and questions surrounding pre-implantation genetic diagnosis were well worth it, knowing their children would be spared from a deadly disease that robs people of their minds and bodies. “I’m mostly afraid of losing who I am and not being able to control it,” said Stacy Brookhyser, as she held baby Laurel on her lap and looked over at her husband, who was holding Roxanne. “They’ll never have to worry about it.” View PDF