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Should prospective parents seek information about gene variants that increase the risk that their children will develop diseases that manifest themselves when they are adults? Should physicians give the information to them? Some bioethicists believe that such testing is wrong, arguing that such information could stigmatize the child and that it may suggest that people with genetic illness predispositions should never have been born. They further argue that children have a right to an "open future" in which they are not burdened with the knowledge of their genetic predispositions for adult onset illnesses.
Consider the situation of Amanda and Bradley Kalinsky, as reported on the front page of The New York Times. Amanda Kalinsky tested positive for the gene that produces Gerstmann-Straussler-Scheinker (GSS) disease, a form of early onset dementia. Several family members, including her father, had already succumbed to the disease. When she found out that she was a carrier, she initially vowed never to have children. Amanda and her husband learned, however, that they could use pre-implantation genetic diagnosis of their embryos to avoid passing along the gene to their kids. Fertility clinic specialists induced her to produce several eggs that were removed and then fertilized with her husband's sperm. The resulting embryos were tested for the GSS gene, and only those which did not have it were implanted her womb. The happy result is that the Kalinskys are the parents of three children that have been spared the prospect of suffering the disease that is likely to kill their mother.
In the Times article, the Yeshiva University bioethicist David Wasserman argues that discarding embryos with that carry deleterious adult onset disease genes is essentially saying that someone like Amanda Kalinsky should never have been born. But decisions about who should be born ought not to be in the hands of ethicists; they should be left up to the people whose lives and values are actually on the line. For Kalinsky, the fact that any of the children she might bear through conventional reproduction could inherit the deleterious GSS gene was a bad enough possible outcome for her to decide never to reproduce. Pre-implantation genetic diagnosis enabled her and her husband to have children like her but without the prospect of suffering the disease. Either way, the child with the GSS gene was not going to be born; this way, someone still got to be born anyway.
The Kalinskys knew exactly what heritable disease they wanted their prospective children to avoid. Now a new, much more comprehensive whole genome screening test enables researchers and physicians to identify disease risks in developing fetuses that parents might not be aware of, such as genes increasing the possibility of breast cancer or Alzheimer's disease. The new test sequences a fetus' genome based on DNA it sheds into its mother's bloodstream. So researchers can now reveal genetic predispositions ranging from trivial characteristics like hair and eye color and propensity to baldness to the risk of diabetes and cancer.
Is it ethical for physicians to sequence a fetus' genome and then tell parents what the genetic screening test uncovers? Yes, argues Ignatia B. Van den Veyver of Baylor College in the current issue of Prenatal Diagnosis. Among other arguments, Van den Veyver correctly notes that withholding prenatal genetic testing information thwarts the autonomy of parents to make reproductive decisions. With regard to whether such genetic knowledge impair a child's right to an open future, Van den Veyver ponders "whether we infringe autonomy by shielding information that may allow parents and young adults to make decisions about their future that take into consideration all aspects of their current or future health."
Similarly, in the January 16 New England Journal of Medicine, Ilana Yurkiewicz of Harvard Medical School, Lisa Soleymani Lehmann of Brigham and Women's Hospital, and Bruce Korf of the University of Alabama at Birmingham argue that it is ethical to provide parents with prenatal whole genome sequencing information about their prospective children. They write that it is "a basic right of reproductive choice and parental autonomy; people may choose when, with whom, and how to reproduce, and they have the right to data that may inform these decisions." The trio also notes that women in the United States do not have to provide a reason for obtaining an abortion, so it is "difficult to justify restricting abortion in the case of a well-defined reason, such as genetic disease."
They also reject the notion that genetic ignorance is somehow liberating. "Instead of limiting a child's potential future, knowledge of genetic risks can offer a greater opportunity to inform possibilities for a good life," they point out. And that's the essential point: Whatever some bioethicists might believe, autonomy is never enhanced by ignorance.
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