|UT Southwestern's Eric Olson|
Notch up another big score for CRISPR/Cas9 gene-editing technology. Already one of the hottest new technologies in the lab, a group of investigators at UT Southwestern used CRISPR/Cas9 to correct a genetic mutation that causes fatal cases of Duchenne muscular dystrophy.
Dr. Eric Olson's team at UT Southwestern already used CRISPR/Cas9 to do a germ line correction in mice to prevent muscular dystrophy in 2014. For humans, though, they need to work with postnatal tissue. And in this case they used adeno-associated virus 9 (AAV9) to deliver the editing components to the rodents, snipping out a defective exon that prevents the production of dystrophin, which triggers the disease.
Once treated, the mice began to produce the dystrophin they needed. The results were published in Science.
Now the investigators want to move ahead, testing the tech on human cells from patients as well as larger animal models before considering the possibility of launching human tests. And significantly, two other academic teams--at Duke and Harvard--independently accomplished the same thing on their own, highlighting the validity of the approach.
Over recent years several biotechs like Sarepta, BioMarin and PTC have been advancing new therapies designed to spur production of dystrophin, but much of the data have been bad or involve such small groups of patients that big doubts about their overall effectiveness cloud the field. If a CRISPR/Cas9 approach like this can work to cure the disease, all of these other efforts will be sidelines.
But moving from a preclinical approach to a proven cure will take plenty of painstaking work.
"The CRISPR/Cas9 system is an adaptive immune system of single-celled organisms against invading virus. Ironically, this system was hijacked, we packaged it into a nonpathogenic virus, and corrected a genetic mutation in an animal model," said Dr. Long.