The age-old axiom “time will tell” may not be so true anymore. Thanks to the growing technology of human genome sequencing and its shrinking price, it is becoming easier than ever to know one’s genetic “future.
As the price of whole genome sequencing continues to fall, DNA screenings are becoming readily available to people who require it, such as those who are pre-disposed to fatal diseases. At the same time, experts are becoming increasingly skeptical about some of the uses of genome sequencing. Last summer, the New York Times reported that the first prenatal human genome was sequenced. Although this is a major step for couples at risk of having a child with genetic diseases, critics argue that it is a completely uncalled-for technique that will harm society rather than help it.
Until now, the technology of diagnosing disease in a fetus was limited to screening for specific genes that would immediately affect the fetus. However, with prenatal whole genome sequencing, information that is arguably unnecessary for the immediate welfare of the parents and the child is revealed. When sequencing a genome, there are known genes that code for carrier genes and predisposition genes, and there are still many genes that are not completely understood or related to observed traits. A predisposition gene can be helpful for adults that have a documented family history of a cancer and want to check their own likelihood of contracting it. Yet experts worry that because there are so many lethal genes in each person’s DNA, if parents are told that their child has certain predisposition or carrier genes, or even a gene that is linked to aggressive behavior; the parents may immediately panic from the overwhelming information and choose to abort a normal fetus. Most human genomes do contain mutations and a degree of lethality, but to the average layperson, this information is worrisome.
Another objection to whole genome sequencing of a fetus is that an unborn child will lose his or her “right to know” and future autonomy. A person will know his/her susceptibility to develop late onset conditions which can cause anxiety as this child grows up. Therefore, some argue that the only information parents should be given is only that which will have an immediate impact on their lives or their child’s life. Of course, the issue of what should be included in this delicate category is one laden with deep ethical questions and ramifications, and must be studied further and codified.
If prenatal genome sequencing would become a common practice for every expecting couple, the fear of some sort of “eugenics” would also arise. Eugenics, or the theory of improving the genetic quality of the population by promoting the reproduction of people with desired traits, was a popular theory in Nazi Germany. In recent times, the issue of eugenics became relevant when experts were considering pre-implantation genetic diagnosis (PGD). PGD is a process that is not dissimilar to whole genome sequencing. PGD is done during in vitro fertilization as a means to diagnose embryos before they are selected and implanted. After an egg is fertilized in the laboratory, it grows into an embryo with more cells. Once the embryo is a couple of days old, a cell is removed from the embryo and its DNA is tested. If the cell’s DNA is found to be problematic, that embryo will not be implanted into the mother. The process can be used for diagnosing heritable diseases, such as Huntington’s disease. It is specific to the mutations that the doctor and researchers search for.
PGD has also been used to choose the gender of an embryo before it is implanted. Some worry that this technology would lead to a skewed ratio of men to women. For example, in Israel, to assure that this sex selection does not cause a skewed population, there is a rigorous process to get pre-approved for sex selection. Each couple requesting sex selection must get their request approved by a specially appointed board. This board determines case-by-case if the sex selection should be permitted. The skepticism that surrounds the possible negative outcomes of PGD— such as a skewed population and eugenics — is indicative of the opposition that accompanies pre-natal whole genome sequencing, a more extensive and informative process.
Although technology is advancing rapidly, it is important for parents to carefully consider and analyze the benefits and risks of deciding whether or not to sequence a genome prenatally. Undoubtedly, the affordability of such a technique is exciting to some but is an ethical question that must be challenged. As more and more cutting-edge technologies become available to our generation, we have to realize that great responsibility should always accompany knowledge.