National Panel Says "Yes" to Gene Therapy Procedure, but With Restrictions

Each week breaking news announce discoveries in research and technology, fueling new hope for patients with difficult diseases. But just because something is possible, should it be done? That question hounds cutting-edge therapies such as Mitochondrial Replacement Therapy (MRT), that promises to allow patients with mitochondrial disease - a group of highly variable disorders that can cause muscle weakness, heart disease, blindness, dementia and other health issues - to have children who are free of their often-debilitating burden. The modified in vitro fertilization technique creates an embryo with DNA from two parents and healthy mitochondria from a third donor.

The technology carries with it a host of questions that reflect the ethical and scientific gray areas it currently falls into. If scientists perform genetic manipulations on an embryo that will be inherited by future generations, is that equivalent to “playing God?” How much research should be done before the approach is considered safe? Why not avoid these issues altogether by encouraging adoption or egg donation instead?

“People want to have genetically related children,” says medical ethicist and Utah Genome Project investigator Jeffrey Botkin, M.D. He is also director of the University of Utah Center for Excellence in Ethical Social and Legal Implications in Genetic Research (UCEER). “Given the alternative ways couples can build a family, the question is, ‘How important is it as a society to help couples with mitochondrial disease by manipulating embryos?’”

Last year, the British parliament passed a measure allowing certain patients to undergo the procedure. Here in the U.S., the National Academies of Sciences, Engineering and Medicine (formerly the Institute of Medicine) recently concurred that MRT is “ethically permissible”, but only if precautions are taken. They recommend that only male embryos be implanted for possible pregnancy. Because mitochondria are inherited exclusively from the mother, the safeguard throws up a natural block: a male would be unable to pass his donor mitochondria, and potential complications caused by it, to his children. The guidelines were created upon request from the U.S. Federal Drug Agency.

“We though that was the appropriate compromise at this point,” says Botkin, a member of the expert panel. “First we’ll find out how safe it is with male embryos before moving on to female embryos.” It’s still possible the technology will be considered unsuitable for helping mothers with mitochondrial disease to have families. The panel says the procedure needs to be tested extensively in the laboratory first.

While these recommendations were being developed, another group of experts were hotly debating whether we are ready to use gene-editing technologies, such as the new easy and efficient CRISPR/Cas9, to prevent children from inheriting any one of hundreds of genetic diseases. This type of gene therapy is different from MRT, but the two are similar in that they could both permanently alter the human gene pool. The second group arrived on a stricter stance, calling for a research moratorium on heritable gene-editing due to concerns that at present the risks are too high.

Though careful consideration went into both consensus statements, for now they are merely thought experiments. Last December, a budget bill was passed that prevents the FDA from moving forward on mitochondrial and other heritable gene therapies. In the interim until the amendment to the bill is once again up for negotation, efforts are underway to continue the conversation on a broader scale, engaging patient advocacy groups and other stakeholders.

When it comes to answering the question, “Can we do it?” science is increasingly saying “yes”. But the answer to, “Should we do it?” is not so straightforward. "It’s a decision that both science and society must agree on," says Botkin.

 

 

 


 

Just because we can, should we?

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