A new study is the first to demonstrate the genetic editing technique Crispr could be used to restore faulty genes with healthy ones. The research, which was carried out on blind animals, found that scientists were able to partially restore vision. Scientists claim that this technique could be used in future on patients with a wide range of genetic conditions.
The procedure has previously only been used for diving cells, and there have been struggles in research to apply it to non-dividing cells, which include most adult tissue including the brain, heart and liver. The latest development gives hope that the technique could be used to treat a range of illnesses in adults, including cystic fibrosis and muscular dystrophy.
Professor Juan Carlos Izpisua Belmonte, who led the study, said “For the first time, we can enter into cells that do not divide and modify the DNA at will. The possible applications of this discovery are vast.” Researchers plan to trial the technique in humans in the near future, and it could be in as little as two years.
Crispr is often referred to a “molecular scissors”, and has already been considered one of the biggest breakthroughs in genetic editing as it allows specific parts of DNA to be replaced by artificial, yet healthy versions of genes. However, scientists have yet to achieve successful editing on DNA that’s less accessible, and haven’t managed to use the technique to treat genetic disorders in adults of children.
In stable cells in living organisms, however, the DNA is less accessible, and scientists had not managed to achieve the same “cut and paste” editing. This meant that while Crispr could potentially be used to remove genetic mutations from embryos it not clear whether it also could be harnessed as a therapy for children and adults with genetic disorders.
This study was carried out on rats, and found that Crispr could be used to treat retinitis pigmentosa – which is a form of genetic blindness. The scientists found that they could target retinal cells by injecting gene editing substances into the eye. The rats showed response to light, and tests indicated some improvement in the function of retinal cells.
Co-lead author Reyna Hernandez-Benitez commented “We were able to improve the vision of these blind rats. This early success suggests that this technology is very promising.” It’s thought that the treatment could be given earlier in humans in order to be more efficient, as the study found only 5% of faulty genes had been replaced in the trials.
Professor Robert MacLaren, who works on gene therapy at the University of Oxford and was not part of the study, said: “Getting the DNA into cells that are not dividing is quite an advance. This has got huge potential.”However, he said that the timeline for treatment being applied to humans was “extremely optimistic”.