Two scientists said this week’s news of the successful editing of human embryos’ DNA to erase an inheritable heart condition shows potential in preventing disease. However, both urged caution and said there is more work to be done to ensure the process is safe.

W. Andrew Faucett, the Genomic Medicine Institute professor and director of policy and education at Geisinger Health System in Danville, Pa., and F. Daniel Davis, Geisinger’s chief bioethics officer, were not greatly concerned, however, that the research would lead to genetic manipulation to produce so-called designer babies.

Faucett and Davis were responding to reports this week that the first gene editing on human embryos that has been conducted in the United States. Researchers said that they consider their work very basic: Embryos were allowed to grow for only a few days and there was never any intention to implant them to create a pregnancy. The goal, though, is to “correct” disease-causing genes in embryos.

Details of the experiment using the laboratory tool known as CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats), a type of “molecular scissors,” became public Wednesday with the release of paper in the journal, Nature.

“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.”

Researchers used eggs from a dozen 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 it 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. Geisinger announced in June its MyCode Community Health Initiative — which studies the DNA of patient-participants — surpassed 150,000 participants with a new goal of 250,000 enrollees. The initiative involves patients at Geisinger Health System locations in Pennsylvania and New Jersey, where a biobank stores blood and other samples, allowing for analysis of DNA by Geisinger and collaborators. The health system serves more than three million patients throughout 45 Pennsylvania counties and southern New Jersey on 12 campuses and two research centers.

“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.

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.

Sylvester writes for the Sunbury, Pennsylvania Daily Item. The Washington Post contributed to this article.