10. 01. 2018
Two types of Cas9 protein, with which DNA helix is checked and cut, are not suitable for everyone. In a study involving 12 adults and 22 newborns, scientists found that more than 65% of them have T cells that protect the body from the effects of Cas9. This is a disappointing forecast for the development of gene editing. It may well be that the removal of mutations in most people will become impossible. Immunity of people who have antibodies in the body of two types of necessary protein, simply will not allow the use of CRISPR therapy. And in the worst case — will lead to serious damage to the body with toxins.
This is partly because the Cas9 protein was obtained by combining two bacteria (Staphylococcus aureus and pyogenic streptococcus). These bacteria often attack the body, and therefore the immune system has learned to recognize them.
Attempts to solve this problem will consist in finding a new technology CRISPR, which will use new types of bacteria, those that the body has not yet encountered.
Most recently, gene editing was first applied to a living person. A forty-four-year-old man with Hunter syndrome underwent a genome editing procedure. He was injected intravenously with billions of copies of corrective genes, as well as what was supposed to cut DNA in certain places. DNA was cut, the gene was inserted and sewn up. The process is irreversible. But the patient has already transferred 26 operations, and for him — this is the last chance.