CRISPR is capable of targeting specific stretches of genetic code and editing DNA. Researchers have used the tool to erase a genetic mutation that causes hypertrophic cardiomyopathy in human embryos.
The study, published in Nature, represents a step forward in the application and accuracy of CRISPR.
Led Shoukhrat Mitalipov, with the Oregon Health and Science University in Portland, the research focused on 58 human embryos that were not going to be implanted. Of the 58 embryos fertilized with sperm containing MYBPC3, the gene mutation for cardiomyopathy, 42 were successfully modified to contain two normal copies of the gene.
In a release from Nature, developmental biologist Robin Lovell-Badge of the Francis Crick Institute in London noted ethical concerns about so-called “designer babies,” where parents can mix and match genetic information to get their ideal child. But such worries are unfounded—or at least not a concern at this time.
“This isn’t a clear step towards a designer baby,” said Lovell-Badge. “This suggests that you couldn’t add anything that wasn’t already there.”