For several weeks, rumors have been circulating that a research group in China had performed the first targeted editing of DNA in human embryos. Today, the rumors were confirmed by the appearance of a paper in the journal Protein & Cell, describing genome editing performed at Sun Yat-sen University in Guangzhou, China. The paper shows that while the technique can work, it doesn't work very efficiently, suggesting there are a lot of hurdles between existing techniques and widespread genetic engineering of humanity.
To avoid potential ethical issues, the researchers performed their experiments with embryos that had been fertilized by more than one sperm. While these are regular occurrences in in vitro fertilization procedures, the embryos are inviable and normally discarded. This prevented any chance that an edited embryo could somehow produce a viable, adult human.
The work relied on the CRISPR-Cas9 system. This allows the researchers to inject DNA that encodes an enzyme and targeting RNA into a cell, which then cuts a specific DNA sequence (see the sidebar for details). The cut then typically gets repaired using DNA that looks similar. If researchers supply engineered DNA with regions of similarity at the same time as the enzyme, then the edited DNA can be used for repair, integrating it into the genome.
Read 8 remaining paragraphs | Comments
No comments:
Post a Comment