Genetic Risks: The Implications of Embryo Screening
A controversial procedure that lets would-be parents test embryos for certain genetic defects will soon be allowed in special cases in Germany. What does this mean for society?
Do people have the right to a healthy child? "No," says Tina Stark, "they don't."
Her daughter Maya, an eight-month-old with strawberry blonde hair, is lying on the changing table in front of her. It's Tuesday, and Stark has to replace the dressing on her daughter's central venous catheter. She puts on a surgical mask, disinfects her hands and removes the adhesive bandage on Maya's chest. "What we want is not a healthy child," says Stark. "We want a child that doesn't have this disease."
Maya has congenital nephrotic syndrome. Her kidneys allow proteins to pass through her body unused. Nutrients flow through the child like water, which is why she receives infusions at night. Maya needs almost a dozen medications and nutrient solutions to survive. The placement and removal of the tubes takes four hours a day. The Starks have yet to find a nursing service that does this well.
Maya needs to gain weight. She needs to add about nine kilograms (20 lbs.) of body weight to receive a donor kidney, but only weighs seven-and-a-half kilos now. Maya won't live much longer without a new kidney.
Stark, 35, is a teacher, and her husband Andreas, 36, is an anesthesiologist. When she became pregnant with Maya, they chose not to have prenatal screening procedures, such as a nuchal scan and amniotic fluid test. "We would have kept the child in any case, so we didn't need to know anything," say the Starks.
Today they are certain that the congenital disorder would not have been detected in a screening. Only one in 100,000 children in Germany is born with the rare syndrome. The outlook for the Starks, however, is completely different. If they have another baby, there is a one-in-three chance that it will have the disease, which is why they recently visited the Medical Genetics Center (MGZ) in Munich.
A Legal Gray Zone
Elke Holinski-Feder, 51, founded the MGZ 12 years ago. A doctor specializing in human genetics, she has degrees in medicine and chemistry and is a professor at the Ludwig Maximilian University of Munich. "Do you know what advice these families are usually given?" she asks. "Try it, and if it goes wrong, terminate the pregnancy!" It isn't the sort of advice Holinski-Feder wants to give her patients. She offers families a different solution instead.
The procedure on which Tina and Andreas Stark are pinning their hopes is called pre-implantation genetic diagnosis, or PID, where an embryo is tested for possible life-threatening genetic defects before it is implanted into a woman's uterus. The procedure could be used to rule out congenital nephrotic syndrome.
The MGZ has been performing PID since the summer of 2010. Holinski-Feder has already provided the genetic test to 82 couples, but until now she has been operating in a legal gray zone.
The legal situation was long unclear. Fearing criminal prosecution, many German doctors did not offer the procedure, shamefacedly sending couples to the UK, Belgium or the Czech Republic.
In 2006, a Berlin doctor reported himself to the authorities. He wanted the country's highest judges to issue a ruling on PID. In 2010, the Federal Court of Justice declared the genetic test permissible in exceptional cases, and a year later the German parliament, the Bundestag, amended the country's Embryo Protection Act.
Last Friday the Bundesrat, the legislative body that represents the German states, approved a rule regulating how the procedure is to be used in practice. If it goes into effect, PID will be permitted in Germany. The German states will then have one year to implement the rule.
What is Normal?
It's been a long road to reach this point. In their conception of what life means and how much control humans should be allowed to exert over it, many critics think this kind of genetic screening is a step too far.
Medical ethicist Axel Bauer writes about his concerns in an article for an initiative called "Stop PID." He fears "that the possibilities PID offers will significantly reduce the range of 'normality' that will still be tolerated in our society in the future." Hubert Hüppe, the federal government's commissioner for the disabled, says critically: "In the future, human life will only exist after quality control."
Elke Holinski-Feder exhales deeply. Then she says: "I have a feeling that many of those who pass judgment on PID don't know what we are doing here."
When doctors, philosophers and politicians talk about PID, they are usually talking about the future. What happens when man begins to qualitatively assess the life he creates in a Petri dish? Is he toying with fate? Playing God? Is he helping? And where do his limits lie?
Holinski-Feder prefers to talk about the present. She is blonde and petite, and there are photos of her children in her office. When her students ask her: "When does human life begin?" she responds with a series of questions: "Imagine you were asked to place a picture of yourself as a child on the shelf. Which picture would you use? The zygote? The embryo? The baby?"
The staff at the MGZ includes five human geneticists and 14 biologists and chemists. The center's main activity lies in the diagnosis of neurogenetic diseases and hereditary forms of cancer. It receives about 30 blood samples a day, mostly from cancer and epilepsy patients. But parents who are carriers of a serious congenital disorder also contact the MGZ for help. Holinski-Feder often has to give them bad news. That is something she wants to see changed -- she wants to give good news, as well.
A Last Chance
One of the couples she would like to be giving good news to are Jürgen Schäfer, 41, and his wife Carola(*), 42, who are currently sitting in the consultation room.
They have traveled to Munich from a small town near Darmstadt in southwestern Germany. A file on the table in front of the Schäfers tells the couple's story, page by page.
They tried to conceive a child for three years. They went to a fertility clinic in the fourth year, and Carola Schäfer underwent an artificial insemination procedure twice. Then she became pregnant.
When her doctor performed an ultrasound in the 14th week of pregnancy, she discovered a kink in the child's spine. A sample of amniotic fluid was taken in the 18th week. By the 20th week, it was clear that the child had an unbalanced translocation on the second and 16th chromosomes. It had severe organic damage. The cerebellum wasn't growing, the heart was too large and the large intestine was missing.
The doctors told the parents: "It's very likely that it won't survive." Birth was induced prematurely in the 21st week, and the child died shortly after delivery.
After they overcame the shock, the Schäfers went to university hospitals and genetic specialists to try to find out what could be done so that they wouldn't have to experience the same thing again. "We were in Munich, Bonn, Lübeck and Wiesbaden," says Jürgen Schäfer. "They all referred us to someone else." If they hadn't found the MGZ, the Schäfers would have gone to Belgium.
Holinski-Feder explains to the Schäfers how PID is done. A fertility center removes oocytes, or immature egg cells, from the woman and artificially inseminates them. On the fifth day of development, a few of the cells that are emerging from the shell are extracted. These cells have the same genetic material as the embryo, but they develop into placenta. The procedure is called trophectoderm biopsy. By examining these cells, the MGZ can determine whether an embryo has inherited certain genetic defects.
"If we don't try this now," says Jürgen Schäfer, "we'll regret it for the rest of our lives."
They walk out of the doctor's office and go to the coat closet. Jürgen Schäfer gets their jackets so that he can help his wife put hers on. Carola Schäfer is sitting in a chair, and her husband sits down next to her. Then she leans her face against his shoulder and begins to cry.
- Part 1: The Implications of Embryo Screening
- Part 2: 'All We Have Is a Few Cells'
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