[SIZE=7]Diseases CRISPR Technology Could Cure[/SIZE]
CRISPR-Cas9 was first used as a gene editing tool in 2012. In just a few years, the technology has exploded in popularity thanks to its promise of making gene editing much faster, cheaper and easierthan ever before.
CRISPR has already changed the way scientists do research. But what everyone is expecting, either with excitement or fear, is its use in humans. In theory, CRISPR technology could let us edit any genetic mutation at will, curing the disease it causes. In practice, we are just at the beginning of the development of CRISPR as a therapy and there are still many unknowns.
But if you had at least a chance to cure any genetic disease, which one would it be? These are seven diseases that scientists are already tackling with the help of CRISPR-Cas9, and which could eventually become the first conditions to ever be treated with this revolutionary technology.
[SIZE=7] Cancer[/SIZE]
The first applications of CRISPR could be in cancer. Indeed, one of the first and most advanced CRISPR clinical trials, which is currently running in China, is testing the potential of the gene editing tool to treat patients with advanced cancer of the esophagus.
The treatment being tested at the Hangzhou Cancer Hospital starts with the extraction of immune T cells from the patient. Using CRISPR, the cells are modified to remove the gene that encodes for a protein called PD-1 — some tumors are able to bind to this protein on the surface of immune cell and instruct them not to attack. The modified cells are then reinfused into the patient with a higher capacity to attack cancer cells.
So far, at least 86 people with different forms of cancer have been treated with CRISPR in China. In the US, another CRISPR trial, with the first patients treated in April 2019, also targets cancer. Scientists at the University of Pennsylvania are using CRISPR to remove PD-1 as well as to change a molecule on the surface of immune cells to make them find and attack tumors.
[SIZE=7]AIDS[/SIZE]
There are several ways CRISPR technology could help us in the fight against AIDS. One is using CRISPR to cut the DNA of the HIV virus out of its hiding place in the DNA of immune cells. This approach could be used to attack the virus in its hidden, inactive form, which is what makes it impossible for most therapies to completely get rid of the virus.
Another approach could make us resistant to HIV infections. Certain individuals are born with a natural resistance to HIV thanks to a mutation in a gene known as CCR5, which encodes for a protein on the surface of immune cells that HIV uses as an entry point to infect the cells. The mutation changes the structure of the protein so that the virus is no longer able to bind to it.
This approach was used in a very controversial case in China last year. CRISPR-Cas9 was used to edit human embryos to make them resistant to HIV infections. The experiment caused outrage among the scientific community, with some studies pointing out that the ‘CRISPR babies’ might be at a higher risk of dying younger. The general consensus seems to be that more research is needed before this
[SIZE=7]Blindness[/SIZE]
CRISPR is a great candidate to treat genetic blindness. Many hereditary forms of blindness are caused by a specific mutation, making it easy to instruct CRISPR-Cas9 to target and modify a single gene.
In addition, the eye is an immunoprivileged part of the body, meaning that the immune system’s activity is limited there. This becomes an advantage in sight of the concerns regarding the possibility that CRISPR could induce immune reactions against it, which would block its activity and derive into side effects.
Editas Medicine is working on a CRISPR therapy for Leber congenital amaurosis, the most common cause of inherited childhood blindness, for which there is no treatment. The company aims to target the most frequent mutation behind the disease, using CRISPR to restore the function of light-sensitive cells before the children lose sight completely.
[SIZE=7]Blood disorders[/SIZE]
The first CRISPR trial in Europe and the US, which enrolled its first patient in February this year, aims to treat beta-thalassemia and sickle cell disease, two blood disorders that affect oxygen transport in the blood. The therapy, developed by CRISPR Therapeutics and Vertex Pharmaceuticals, consists in harvesting bone marrow stem cells from the patient and using CRISPR technology to make them produce fetal hemoglobin, a natural form of the oxygen-carrying protein that binds oxygen much better than the adult form.
Before the trial started, the FDA put it on hold in the US to clear out some safety questions. A few months later, the hold was lifted and the treatment was given fast track designation for both conditions.
Hemophilia is another blood disorder that CRISPR technology could tackle. CRISPR Therapeutics is working with Casebia on an in vivo CRISPR therapy where the gene editing tool is delivered directly to the liver.