Researchers from Portland, Ore. genetically modified human embryos for the first time on American soil, but this is not a new feat. The process has already been done in China. To date, no genetically modified embryo has been inserted into a womb.
The lead researcher, Shoukhrat Mitalipov of Oregon Health and Science University, has a history of embryo work and demonstrated this round that it’s possible to safely remove inherited diseases by changing defective genes. This is called “germline engineering.” However, none of the embryos were allowed to last longer than a few days and the results are still pending publication.
Germline engineering typically uses CRISPR-Cas9, technology which precisely alters DNA. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats.
At its roots, CRISPR is comprised of a small piece of RNA and a protein called Cas9. The RNA is preprogrammed to match a specific genetic code to then subsequently alter a specific strand of DNA once injected. The RNA guides the injection, and Cas9 tags along because, as an enzyme, it is able to break the DNA at an exact spot.
The challenge is that DNA tends to repair itself pretty fast. To avoid this, some CRISPR injections carry another strand of DNA the cell can use to fix the break that’s created, therefore allowing genetic alterations.
“The implications are very large,” Dr. Charles Murry, Director of the UW Medicine’s Institute for Stem Cell and Regenerative Medicine, said. “It gives us the ability to permanently eradicate a genetic disease from a family’s pedigree. And as a physician, that’s something that’s extremely exciting to me.”
Genetic modifications have been around for decades, and CRISPR has applied since early 2013. The possibilities for CRISPR were first realized through a natural bacterial process that defends against invasive viruses — also known as “this all started with yogurt,” surprise.
However, the real breakthrough happened in 2015 with Junjiu Huang’s first human embryo edits in China. Scientists are also looking at this system to eliminate pests and the diseases they carry.
“There’s another side to it of course,” Murry contended. “When humans begin to rewrite our own genetic code, and there are all kinds of chances to not only make corrections as we edit but to make new mistakes as we edit … we may inadvertently create problems in the attempt to solve others.”
UW Health Sciences and Medicine public information editor Leila Gray said UW Medicine researchers are using CRISPR on specific somatic cells, which are the ones that make up your body. These cells were collected from patients with their approval. One team, for example, is trying to edit cells with kidney disease, studying certain conditions in petri dishes. But no UW researcher is reporting work to remove genetic diseases from human embryos.
Currently, the National Institutes of Health won’t federally fund this research. However, the National Academy of Sciences and the National Academy of Medicine are recommending cautious reconsideration.
Murry predicts that before any of this would apply to a human being, a large animal would have to successfully carry to term a genetically modified embryo. Scientists would also likely have to monitor the newborn’s life afterward.
There are ethical conundrums with this new technology. It’s so concerning that upon its first big embryonic debut, there was a three-day summit in December 2015 for hundreds of local and global scientists, policymakers, and the US presidential science adviser.
Some worry genetic engineering could lead to a dark future where humans are pre-edited for appearance, physical strength, or intelligence.
George Church, a Harvard Medical School geneticist, first told the Washington Post two years ago that there were nearly 2,000 genetic therapy trials already underway that didn’t use CRISPR. The difference between those and the few that have is cost.
“It’s about 1,000 times cheaper for an ordinary academic to do,” Church is quoted in the article. “It could be a game-changer.”
Reach reporter Kelsey Hamlin at email@example.com. Twitter: @ItsKelseyHamlin