A group of scientists from the University of California at Berkeley published an article in the journal Science Advances, which describes a successful experiment on the gene therapy of Lou Gehrig's disease (amyotrophic lateral sclerosis, ALS) in mice. Using CRISPR / Cas9 genome editing technology, scientists have extended the lives of GM-mice with SOD1 gene mutation, which accounts for 2% of cases of ALS in humans.

Mutation in the SOD gene leads to the rejection of the spinal cord and muscles. In most patients with ALS, the development of the disease begins with paralysis of the limbs and eventually leads to loss of respiratory function and death. True, in rare cases the disease stabilizes; this happened in the famous physicist Stephen Hawking, who, having lost control of the body, continues to breathe independently. Not all cases of ALS are due to a mutation in the SOD gene, in many cases the cause of the disease is not at all clear.

For targeted delivery of the system to the neurons of the spinal cord CRISPR / Cas9 in the body of mice, scientists used harmless adenoviruses. Once in the right cells, the system cut out the mutant parts of the genome, and then the cells themselves restored the damaged strands, filling them with the correct, unmutated sequence of nucleotides.

The mice did not recover completely, but their development slowed, and they lived a quarter of a year longer. An autopsy showed that neurons in which the genome editing passed without errors survived in mice; neighboring cells, which were not targeted adenoviruses, died.

The authors of the work note that their experiment is not a ready-made technique of therapy, but only the beginning of a large path. Scientists have yet to learn how to deliver the CRISPR / Cas9 system to all cells that are threatened with die-off due to mutation.

Source: PM.