Korean Team Advance CRISPR Safety
Anti-cancer cell therapies and the end of the CRISPR-Cas9 controversy.
The Institute for Basic Science (IBS), Center for Genome Engineering, with Seoul National University College of Medicine and ToolGen, has developed a new technique that may progress CRISPR-Cas9 as a tool to develop anticancer cell therapies.
Up until now, there have been safety concerns regarding CRISPR-Cas9. Specifically, there has been a fear that CRISPR-Cas9 may induce cancer-causing mutations in off-target sequences that are similar to on-target sequences.
The researchers have developed a technique termed Digenome-seq to locate both on-target and off-target sequences that can be mutated by CRISPR-Cas9 via genome sequencing. They digested human genomic DNA using Cas9 nucleases in a test tube, which was then subjected by whole genome sequencing. This in vitro digest yielded a unique pattern at both on-target and off-target sequences that can be computationally identified. Furthermore, by adding guanine nucleotides at the end of sgRNA(single guided RNA) that composes CRISPR-Cas9, they have successfully created this highly-developed programmable nuclease, which has no measurable off-target effects in the human genome.
Jin-Soo Kim, the director of the Center for Genome Engineering at IBS, as well as the professor of the Department of Chemistry at Seoul National University says, “If CRISPR-Cas9 truncates off-target DNA sequences, it might induce unwanted mutations. Since we have succeeded in confirming the accuracy of CRISPR-Cas9, we anticipate that there will be a great progress in the development of gene or cell therapies.”