While the genome editing method CRISPR is groundbreaking, it is unfortunately not yet perfect.It may lead to the emergence of mutations in random sites of the genome and is only applicable to a limited part of it.Various scientific groups are carrying out continuous research on improving the performance of this tool and everything seems to indicate that one of them has already succeeded.
A team led by David Liu, a chemist of Harvard University, have elaborated a variant of CRISPR that is potentially much more precise.
"It is an impressive and highly important finding", emphasises Erik Sontheimer of the Medical School of the University of Massachusetts in Worcester himself, a CRISPR pioneer.
So far, the aforementioned genome editing method harnessed spCas9 enzyme that is naturally present in the bacterium named Streptococcus pyogenes.However, the use of it also involved certain limitations, as it was only applicable to specific sections of the genome that are characterised by the presence of a particular sequence.The new finding modifies the enzyme to create xCas9 which will allow for subjecting even 4 times more sites to genome editing than before.
What benefits may the research results bring about?First of all, the outcome of the research provides access to previously inaccessible genes, such as those encoding chronic diseases.However, quite apart from his general excitement, the researcher emphasises that we cannot overlook one thing: the enzyme Cas9 is a natural component of a bacterial immune strategy and its inappropriate use within a foreign genetic material could simply turn out to be hazardous. Currently, Cas9 requires further study that could ultimately substantiate its superiority over spCas9.
Photo:K.C.Roeyer, University of California