New DNA editing tool could fix up to 89 percent of genetic mutations

2019-10-22 19

CAMBRIDGE, MASSACHUSETTS — Scientists from Harvard University and the Massachusetts Institute of Technology have developed a new method of editing DNA, called prime editing, which combines CRISPR-Cas9 with a reverse transcriptase enzyme.

The CRISPR-Cas9 is used to nick one DNA strand, while the enzyme generates a new DNA strand which is inserted into the original DNA strand, according to a study published in the journal Nature.

Another reverse transcriptase enzyme then guides the CRISPR-Cas9 to nick the other DNA strand. The strand is repaired as the enzyme replicates gene edits over from the new DNA strand, producing a fully editing DNA strand.

According to a Harvard news release, prime editing can also be used to replace one DNA letter with another and could correct up to 89 percent of genetic mutations."

In the study, researchers explained that they used prime editing to make more than 175 edits in human cells in a laboratory and successfully corrected sickle cell anemia and Tay-Sachs disease.

CRISPR-Cas9 if used by itself isn't as precise as prime editing and could lead to mismatched DNA strands that either include extra DNA code or are missing a certain genetic code, according to the Harvard news release.

The authors of the study concluded by saying they will investigate the effects of prime editing on human cells and will continue to test prime editing on cells.