Shoukhrat Mitalipov, director of the Oregon Health & Science University's Center for Embryonic Cell and Gene Therapy, reportedly led the new research. Mitalipov and the university would not confirm details of the research to CNN.

"Results of the peer-reviewed study are expected to be published soon in a scientific journal. No further information will be provided before then," according to an emailed statement from the university's press office. Another researcher cited in the MIT report, the Salk Institute's Jun Wu, did not reply to CNN's request for comment.

Mitalipov also declined to comment in the MIT Technology Review report, referencing that the research results have not been published yet in a peer-reviewed scientific journal, which is considered the gold standard for scientific research. The author of the MIT report would not confirm to CNN whether he had seen the paper.

The MIT Technology Review reported that the researchers in Portland, Oregon, edited the DNA of a large number of one-cell embryos, specifically targeting genes associated with inherited diseases in those embryos. The MIT Technology Review could not determine which disease genes had been chosen for editing in the new research.

"I'm not surprised that they were looking at genetic diseases to try and see if they could target them, because that's exactly where I think the future inevitably leads," said Arthur Caplan, a professor and founding head of the division of bioethics at New York University Langone Medical Center, who was not involved in the research.

When it comes to the new research, "my reaction was, this is an interesting incremental step, and boy, I bet it's going to get blown up as being more important than it is," said Hank Greely, professor of law and genetics at Stanford University, who was not involved in the research.

"It's not the first time anybody has CRISPR-ed human embryos. It's not the first time anybody's CRISPR-ed viable human embryos. It's certainly not the first time people have CRISPR-ed viable mammalian embryos," Greely said. "It's the first time it's been done in the US, but the embryos don't care where they are."

Yet the research has already generated attention and controversy.

"This is pushing the research faster than I thought we would see," said Dana Carroll, professor of biochemistry at the University of Utah, if the MIT Technology Review report rings true. Carroll has used CRISPR in his own studies, but was not involved in the new research.

He pointed out that the new research reportedly involved earlier, more delicate embryos, and CRISPR reportedly was still demonstrated as efficient.

"From the perspective of research that would ultimately make germline editing safer and more effective, the earlier embryos will provide more relevant information," he said.

The controversy surrounding gene-editing in human embryos partly stems from concern that the changes CRISPR makes in DNA can be passed down to the offspring of those embryos later in life, from generation to generation. Down the line, that could possibly impact the genetic makeup of humans in erratic ways.

"There is also considerable concern about off-target effects, such as making mutations at sites in the genome other than the intended target," Carroll said. In other words, an edit made in one area of DNA possibly could cause problems in another, as a ripple or domino effect, which could be concerning.

Though, not all experts are too concerned.

"Some people are worried about, where's this all going to head? Are we going to wind up with super babies and eugenics? And to me, I don't find that an interesting objection. It's too soon for that objection," Caplan said. "Clearly, if we're going to let this research proceed, it's going to be to treat diseases and prevent diseases."

"I hope the applications will be for the treatment of serious diseases and in cases where a sensible alternative is not available, as the National Academies' report proposes," Carroll said.

Greely said: "The National Academy of Sciences came out with a big report on Valentine's Day this year about genome editing in humans, and I thought they very usefully divided it into three categories: basic research, treating living people, and making changes that will pass down from generation to generation."

As for the reported new research, "this is category one. This is basic research," he said. "Category three is the ethically crucial one; this isn't that. We're still a long way from that."

"There are what are called point mutations where you can go in and fix one genetic error. The simpler the genetic error, the easier it might be to try to repair it using a CRISPR gene-insertion technique," Caplan said about genetic diseases.

"I think rather than trying to treat cystic fibrosis, or treat sickle cell, or treat hemophilia, it does make ethical sense to figure out ways to prevent it," he said. "Now, obviously if it's too risky we won't do it. If it's too dangerous or maybe it won't work, we still don't know. We're in the early, early days (of research), but I don't think it's fear of eugenics that should stop us."

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Report: Scientists edit human embryos for first time in US - CNN