If you could prevent a horrible hereditary disease from being passed on to your children, you likely wouldn’t hesitate. A no-brainer, right?

Right?

What if that decision involved a procedure right out of science fiction, something akin to the genetic engineering of Brave New World? What if it gave you the chance not only to stop muscular dystrophy or cystic fibrosis in their genetic tracks, but also to ensure your little boy would grow up to be 6’8” with extraordinary athleticism, or your little girl would have superior intelligence and the skilled hands of a surgeon?

What if you could literally create the perfect child? A “designer baby”? Would you?

Such questions have long been within the realm of possibility and plausibility, but this week, the answers to those questions came into much sharper focus — but in a very promising way.

In a study published Wednesday, news broke that “scientists for the first time have successfully edited genes in human embryos to repair a common and serious disease-causing mutation, producing apparently healthy embryos,” according to The New York Times.

“It feels a bit like a ‘one small step for (hu)mans, one giant leap for (hu)mankind’ moment,” Jennifer Doudna, a pioneer of gene-editing techniques, told the Times.

“It’s a pretty exciting piece of science,” George Daley, dean of the Harvard Medical School, told NPR. “It’s a technical tour de force. It’s really remarkable.”

If you’re interested in the technical details, you can read the study in Nature. The specifics of the technique take some effort to understand. But the general concept is clear: in single-cell human embryos, the scientists removed one gene (the MYBPC3 gene) that causes a particularly deadly version of heart disease. The cells then replicated without the gene and the embryos grew, MYBPC3-free.

An article in Futurism notes that treatment “could one day be used to address any of the 10,000 disorders linked to just a single genetic error.”

The ability to eradicate ten thousand disorders? It’s arguably the scientific breakthrough of the year, if not the decade.

The discovery was made possible with CRISPR technology, a method for editing genes. (Learn more about CRISPR from this fascinating podcast from Radiolab, or articles in Vox, Gizmodo, and Wired. See also this library of articles in Science.)

Though a major milestone, the technology is likely a long way from clinical use. The procedure needs to be perfected, and it will undergo intense scrutiny from medical and government authorities before it’s approved. Not to mention the potential ethical issues of such genetic manipulation.

Speaking of ethical issues, what about those embryos used in the study? The embryos, never intended to be brought to full infancy, were created from 12 healthy female donors and sperm from a male who carried the MYBOC3 gene. The defective gene was removed via CRISPR when the sperm was injected into the eggs. The embryos were only allowed to grow for a few days, and none were ever implanted into a womb.

U.S. law prohibits the implantation of edited embryos, and this particular study was within guidelines set by the National Academies of Sciences, Engineering, and Medicine.

University of Wisconsin-Madison bioethicist Alta Charo told The Washington Post that the study represents “a fascinating, important, and rather impressive incremental step toward learning how to edit embryos safely and precisely.”

Of course, can does not imply should. As new tools and techniques such as CRISPR emerge, where do we draw the line between the possible and permissible? Who gets to draw that line? What role in that discussion should ordinary citizens play in a participative democracy?

There’s another question to ask: How will the ability to edit the human genome change our sense of what it means to be human in the first place? If the genome is like code that can be reprogrammed, and new versions of human identity begin to emerge like updates of your iPhone operating system, what does that imply for the rest of us? Were we merely the “beta” versions?

As Charo told the Post, “[T]his is not the dawn of the era of the designer baby.” The technology is not yet far enough along. If current developments are any indication, though, it will be soon.

“This is a harbinger of what’s to come,” biochemist Doudna told Scientific American. “This underscores the important discussion that needs to happen right now.”

Brave New World? Or Brilliant New Breakthrough? What do you think? Comment your thoughts on our Facebook page.