Three person in vitro fertilization (IVF) was developed in 2016 to treat mitochondrial diseases, and one of the first babies produced using the procedure was born earlier this year in Greece. The practice has both passionate supporters and detractors. Supporters hail it as a miracle breakthrough that can eliminate some deadly inherited diseases and save lives, while critics believe that it can lead to genetic engineering and “designer babies.”
The procedure was legalized in the UK in 2015.
Most people have heard of the process of in vitro fertilization, which consists of collecting mature eggs and sperm from donors and fertilizing the egg in a lab, at which point the fertilized eggs are transferred to a uterus. The process can be done using a woman’s own egg and her partner’s sperm, or entirely anonymous donors can be used.
While mitochondrial diseases can be both debilitating and deadly when they appear, thankfully they are a rare phenomenon, with less than 20,000 cases presenting per year in the U.S. According to the United Mitochondrial Disease Foundation (UMDF), “Mitochondrial diseases result from failures of the mitochondria,” which are “specialized compartments present in every cell of the body (except red blood cells).”
The disease can be difficult to detect and the symptoms can vary. The UMDF says, “the parts of the body, such as the heart, brain, muscles and lungs, requiring the greatest amounts of energy are the most affected. Mitochondrial disease is difficult to diagnose, because it affects each individual differently. Symptoms can include seizures, strokes, severe developmental delays, inability to walk, talk, see, and digest food combined with a host of other complications. If three or more organ systems are involved, mitochondrial disease should be suspected.” It is also a genetic condition and is passed from parents to children in several ways.
Three person IVF is a medical procedure developed to help parents whose genetics will almost guarantee that their children will have a mitochondrial disease. It does this by modifying the enucleated egg of the genetically impaired woman.
The Center for Genetics and Society (CGS) says that, “The techniques work by transferring the nucleus of an affected woman’s egg (or the nucleus of a fertilized embryo) into another woman’s enucleated egg or embryo (from which the nucleus has been removed but the mitochondria remain).” This means that the conceived child will have the DNA of three individuals, rather than the normal two parents. Supporters of the technique argue that this is similar to an organ transplant, while opponents argue it is more akin to genetic modification.
3-person IVF has some record of demonstrated success in countries where the process isn’t legally prohibited. In 2016, when a Jordanian baby was born that contained the DNA from three separate people, the baby was free of the genetic condition called Leigh Syndrome that would’ve been fatal to any child the woman had conceived normally.
Despite the success 3-person IVF has had, there are several unanswered ethical concerns with this fertilization method.
The concerns range from worries that widespread genetic modification could trigger “powerful competitive dynamics within and between societies,” where people and societies are competing to engineer perfect children, or children with traits that are deemed desirable for various reasons, as well as the potential disparities that could develop from the well-to-do elements of society having access to genetic modification that is out of the reach of the lower classes. Further, some argue that genetically modifying one’s children could give rise to a moral obligation to genetically modify every child, in order to give them the best life possible.
Francis Sellers Collins is an American physician-geneticist and was appointed the 16th Director of the National Institutes of Health (NIH) by President Barack Obama had the following to say about human genetic modification. “Evolution has been working toward optimizing the human genone for 3.85 billion years. Do we really think that some small group of human genome tinkerers could do better without all sorts of unintended consequences?”
“There are also issues of equity and justice. Who would have access to this kind of human germline engineering? Do we want to accept the scenario that only those with financial resources get to “improve” the genomes of their children?” he added.
Critics of three-person IVF also argue its proponents aren’t being honest about what is involved. For instance, “they point out that we approve of organ transplants to save lives and argue that mitochondrial replacement is just a transplant of a very small amount of genetic material to save the life of an embryo,” she said. “They fail to recognise that in contrast to other transplant situations the existence of the embryo with defective [genetic material], thus needing a transplant, was intentionally created,” Dr. Margaret Somerville told Australia’s Catholic Weekly last month.
“They also downplay the impact of mtDNA arguing that it just facilitates the development of the embryo and does not determine the resulting human being’s fundamental features,” she added.
In other words, far from being an incidental addition akin to a transplant, mitochondrial DNA can impact the development of a wide variety of traits.
“Major international institutions, for instance, UNESCO, the World Health Organisation (WHO) and the European Parliament have spoken out against allowing any genetic modification that would be passed on to future generations as contravening human dignity and there are calls for such interventions to be universally prohibited. Mitochondrial replacement is such a technology as the genetic changes it effects would be passed on,” Somerville added in a separate op-ed for the same publication.
For these reasons and more, genetically modifying humans is widely prohibited across the world, with over 40 countries explicitly banning it due to the ethical and moral concerns associated with human experimentation.
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