CRISPR technology offers the promise to cure any human genetic disease. Which are the candidates to be the first one?
CRISPR-Cas9 was first described as a gene editing tool in 2012. In just a few years, the technology has exploded in popularity thanks to it’s promise of making genome editing much faster, cheaper and easier than ever before.
CRISPR has already changed the way scientists do research, but what everyone is expecting, either with excitement or fear, is it’s use in humans. In theory, CRISPR technology could let us edit any mutation at will and cure 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, what would it be? There are seven diseases that scientists are already tackling with the help of CRISPR, and which could eventually become some of the first conditions to ever be treated with this revolutionary technology.
One of the first applications of CRISPR could be in cancer. 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 in patients with advanced cancer of the esophagus.
So far, at least 86 people with different forms of cancer have been treated with CRISPR in China, results will be available soon.
- Blood disorders
The first CRISPR trial in Europe will seek to treat beta-thalassemia, a blood disorder that affects oxygen transport in the blood.
Hemophilia is another blood disorder that CRISPR technology is expected to tackle. CRISPR Therapeutics is working with Casebia on an in vivo CRISPR therapy where the gene editing tool is delivered directly to the liver.
CRISPR is a great candidate to treat genetic blindness. For many hereditary forms of blindness, the specific mutations causing the disease are known making it easy to instruct CRISPR-Cas9 to target and modify that gene.
There are several ways CRISPR technology could help us in the fight against AIDS. One is using CRISPR to cut the HIV virus out of the DNA of immune cells. This approach could bring the key advantage of being able to attack the latent form of the virus, which is inserted into our DNA and inactive, making
It impossible for most therapies to target it.
Most CRISPR applications in HIV are in early stages of development, still being tested in animals before a clinical trial on humans can be planned.
- Cystic fibrosis
Cystic fibrosis is a genetic disease that causes severe respiratory problems. Although there are treatments available to deal with the symptoms, the life expectancy for a person with this disease is only around 40 years old.
CRISPR technology could help us get to the origin of the problem by editing the mutations that cause the cystic fibrosis, which are located in a gene called CFTR.
Research has proven that it is possible to use CRISPR in human lung cells derived from patients with cystic fibrosis and fix the most common mutation behind the disease. The next step will be testing it in humans, which both Editas Medicine and CRISPR Therapeutics are doing.
- Muscular dystrophy
Duchenne’s muscular dystrophy is caused by mutations in the DMD gene, which encodes for a protein necessary for the contraction of muscles. Children born with this condition suffer progressive muscle dystrophy, and there is currently no treatment available.
Research in mice has shown CRISPR technology could be used to fix the genetic mutations behind Duchenne’s muscular dystrophy.
Huntington’s disease is a neuro-degenerative condition with a strong genetic component. The disease is caused by an abnormal repetition of a certain DNA sequence within the huntington gene. The higher the number of copies, the earlier the disease will manifest itself.
Treating huntington’s is a tricky one, as any off target effects could have more dangerous consequences on the brain. Scientists are looking at ways to tweak the gene editing tool to make it safer.
It’s difficult to predict the outcome of these first efforts to use CRISPR as a therapy, but as these first attempts progress, more and more indications will certainly be added to the list. One of the biggest challenges to turn this research into real cures is the many unknowns regarding the potential risks of CRISPR therapy. Some scientists are concerned about possible off-target effects, immune reactions to the gene editing tool, or that it could increase the risk of cancer. Only Time Will Tell.