First In Vivo Human Genome Editing to Be Tested in New Clinical Trial

Researchers have edited the human genome before, but always in cells outside the body. Now, biotech company Sangamo Therapeutics is recruiting participants for clinical trials in which patients with hemophilia B, Hurler syndrome, or Hunter syndrome will have the gene coding for one of the enzymes that is non-functional in them stitched into their genomes at double-stranded DNA breaks caused by zinc finger nucleases.

“This is the first time someone could have a new gene put into their liver,” Sangamo President and CEO Sandy Macrae told The Scientist. “It’s a privilege and a responsibility to do” these trials.

One of the diseases Sangamo will focus on is hemophilia B, which is a severe bleeding disorder caused by a defective or absent gene called F9. The gene’s protein product, coagulation factor IX, is an enzyme essential for blood clotting.

Two other clinical trials will focus on Hurler and Hunter syndromes. People with these...