Scientists Modify Human Embryos, Ignite Ethical Firestorm

posted: 04/24/15
by: Discovery.com Staff
Artificial insemination

Researchers in China are under fire today after the publication of a scientific paper detailing their attempt to modify human embryos, a practice that is hotly contested within the scientific community.

The study, helmed by researcher Junjiu Huang, utilized non-viable embryos from a local fertility clinic that would not have been able to develop to the point of a live birth. In the study, researchers attempted to use a method known as CRISPR to edit genetic material and prevent the development of a class of fatal blood disorders known as beta thalassemia.

The experiment failed. Almost 20% of the embryos died; many of the ones that did survive were plagued by genetic errors. "If you want to do it in normal embryos, you need to be close to 100%," Huang says. "That's why we stopped. We still think it's too immature."

Genetic modification has the potential to eradicate devastating genetic disorders, such as sickle cell anemia, neurofibromatosis and Down syndrome. Genetic modification is still in its infancy; critics of the practice point out that the long-term effects of genetic modifications are unknown.

"I believe this is the first report of CRISPR/Cas9 applied to human pre-implantation embryos and as such the study is a landmark, as well as a cautionary tale," George Daley, a Harvard stem-cell biologist, told nature.com. "Their study should be a stern warning to any practitioner who thinks the technology is ready for testing to eradicate disease genes."

Learn more about human embryos:


About the blog:
DSCOVRD: The best of the web, covering space, technology, wildlife and more!
More on