On February 3, 2015, Britain became the first country to allow a therapy called the “three-parent IVF technique,” which is based on in vitro fertilization and allows for the ability to create an embryo with genetic material from three different people.
Three parent IVF is still awaiting FDA approval in the United States, and is geared specifically for women with genetic diseases caused by inherited mutations in the mitochondrial DNA (mtDNA). In a recent Letter to the Editor published in The New England Journal of Medicine, several authors found that the therapy might help up to 2,473 women in the United Kingdom and 12,423 in the U.S., all of whom are at risk for transmitting mtDNA disease. This equates to helping approximately 152 women per year in the UK and 778 women per year in the U.S.
In the therapy, a third party – the “mitochondrial donor” – would supply everything except for maternal and paternal nuclear DNA. This is why mitochondrial donation presents ethical and social considerations, so much so that the Institute of Medicine has formed a new committee just for this topic. Some concerned critics see this as one step closer to creating designer babies, while others worry about the genetic modification of eggs and zygotes. Still others question the payment of mitochondrial donors – will this become a well-compensated system, like egg donation?
In a NEJM Group Open Forum on the topic, hosted by Medstro, the authors of the NEJM letter and experts from many fields have joined to discuss this highly controversial subject, wondering if the benefits outweigh the social and ethical policy challenges.
Anna-Kaisa Niemi, MD, PhD, is a pediatrician and medical geneticist with a background in mitochondrial DNA research. She is serving as an expert on Medstro’s forum and believes that this therapy will eventually be approved in the United States, although it may take years.
“Long term follow-up studies, which are ideal, are likely required before approval,” she says. “However, given the duration of a study like this, it may be that it can first be approved in a similar manner to some new investigational drugs that are used to treat one family at a time. And once more knowledge is gained from the UK and from the experience of possibly treating single families in the U.S., it may reach approval.”
Serena H. Chen, MD, the director of reproductive medicine at the Institute for Reproductive Medicine and Science, agrees, although she pinpoints the high cost of research in the U.S. as a significant barrier for implementing this new therapy. “The accumulation of data from the UK will be a tremendous help in obtaining approval in the U.S.,” she says. “But biggest obstacle we face in all research here in the US is the high cost of performing high quality research and the lack of government and non-commercial funding.”
Key to this issue is also the fact that mitochondrial diseases, while more common than most people think, are still relatively rare – especially those caused by mutations in the mitochondrial DNA. Niemi points out that there are several different diseases caused by changes to the mitochondrial DNA, each of which is different from the next.
“Thus it is impossible to get large enough groups to compare,” Niemi says. “And each individual will be different from another person due to their unique genetic background which makes any comparison difficult. Plus the follow-up needed is long – lifelong, in fact – beyond the initial safety studies.”
Time will certainly tell if 3-parent IVF will change the way we think about fertility in America – likely about a year of time, according to Doug Turnbull, MD, PhD, director of the Wellcome Trust Centre for Mitochondrial Research and co-author of the aforementioned NEJM Letter to the Editor.
“I am aware that the Institute of Medicine is currently reviewing mitochondrial donation on behalf of the FDA,” Turnbull says. “They are reviewing the scientific and ethical aspects in an extensive consultation. The results of that consultation are due next year and only after this will we know if they will recommend mitochondrial donation.”
Join the discussion about the benefits and concerns surrounding mitochondrial donation today, and watch this video of experts considering the nuances of the therapy:
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