Two Geisinger Health System scientists said Wednesday the successful editing of human embryos’ DNA to erase an inheritable heart condition shows potential in preventing disease. But both urged caution and said there is more work to be done to ensure the process is safe.
W. Andrew Faucett, Geisinger Genomic Medicine Institute professor and director of policy and education, and F. Daniel Davis, Geisinger chief bioethics officer, were not greatly concerned, however, that the research would lead to genetic manipulation to produce so-called designer babies.
They were commenting on the first gene editing on human embryos that has been conducted in the United States. The Washington Post reported on Wednesday that researchers said that they consider their work very basic. The embryos were allowed to grow for only a few days and there was never any intention to implant them to create a pregnancy. The ultimate goal, though, is to “correct” disease-causing genes in embryos that will develop into babies.
Details of the experiment using the laboratory tool known as CRISPR (or Clustered Regularly Interspaced Short Palindromic Repeats), a type of “molecular scissors,” became public Wednesday with a paper in the journal Nature, the Post reported.
“I’m certainly not an expert on that end of it,” said Davis, the bioethics officer. “But this does represent an advance along the evolutionary pathway of a technology. It’s a step forward in ways most people would agree represents progress. There still are legitimate concerns about the more widespread use and clinical applications at this point.”
According to The Post, the researchers used eggs from 12 healthy female donors and sperm from a male volunteer who carries the gene that causes hypertrophic cardiomyopathy, a disease of the heart muscles that can cause no symptoms and remain undetected until it causes sudden cardiac death. The researchers snipped out the gene that causes the disease and replaced with a copy of the gene.
Faucett said his concerns include whether the technology could lead to other changes in “off-target” genes that would be passed on to future generations.
“We’ll fix the heart gene but damage a cancer-causing gene,” he said. “We’ll solve this problem but cause another problem.”
Faucett said it’s impossible to weigh one problem against the other because no one knows what the off-target gene is until it shows itself years later.
“There are 20,000 genes in the human body,” he said. “A lot of genes we don’t understand. Part of what we’re doing at Geisinger is trying to understand the use of genes. Also what do you do with the genes you understand.”
He said, though, Geisinger is not doing gene editing research but studying DNA samples to check for potential for disease in patients and their families.
“We’re not studying embryos,” Faucett said.
Davis said concerns about manipulating DNA to create specific humans are overblown.
“I don’t mean to be a naysayer,” he said. “I just think the real ethical concern is about safety and efficacy.”
He has less concern about designer babies than about people that are going to be harmed by technology. He cited bone marrow transplants and hormonal therapy for women that have been harmful to some patients because the treatments were not adequately investigated.
The Post reported that Shoukhrat Mitalipov, one of the lead authors of the paper and a researcher at Oregon Health & Science University, said he is conscious of the need for a larger ethical and legal discussion about genetic modification of humans, but that his team’s work is justified because it involves “correcting” genes rather than changing them.
Faucett was on the American Society of Human Genetics committee that wrote the society’s position paper on the genome editing. The paper, which comes out today and is endorsed by a number of genetic study groups from around the world, states it is against anything but laboratory testing (without humans).
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