Do CRISPR enthusiasts have their head in the sand about the safety of gene editing?
by Sharon Begley
While the 150 experts from industry, academia, the National Institutes of Health, and the Food and Drug Administration were upbeat about the possibility of using genome-editing to treat and even cure sickle cell disease, leukemia, HIV/AIDS, and other blood disorders, there was a skunk at the picnic: an emerging concern that some enthusiastic CRISPR-ers are ignoring growing evidence that CRISPR might inadvertently alter regions of the genome other than the intended ones.
“In the early days of this field, algorithms were generated to predict off-target effects and [made] available on the web,” Joung said. Further research has shown, however, that such algorithms, including one from MIT and one called E-CRISP, “miss a fair number” of off-target effects. “These tools are used in a lot of papers, but they really aren’t very good at predicting where there will be off-target effects,” he said. “We think we can get off-target effects to less than 1 percent, but we need to do better,” especially if genome-editing is to be safely used to treat patients.