This is the second part of our article series about the amazing story of the CRISPR genome editing method. Previously, you could read about the history how CRISPR was discovered and how the process of genome editing works. Now, let me show you the mind-blowing results you can achieve with CRISPR therapy.
1) The Gene-Editing Tool
So you should know that scientists around the world are already using this technique in several of their projects. In addition, global research and development companies started using CRISPR/Cas 9 for the development of drugs to treat a number of life-threatening medical conditions, including sickle-cell anaemia and cancer.
For example, Columbia University Medical Center (CUMC) and University of Iowa scientists have used CRISPR to repair a genetic mutation responsible for retinitis pigmentosa (RP), an inherited condition that causes the retina to degrade and leads to blindness in at least 1.5 million cases worldwide. The researchers published their study about it in Scientific Reports.
The authors of the study said that: “We still have some way to go, but we believe that the first therapeutic use of CRISPR will be to treat an eye disease. Here we have demonstrated that the initial steps are feasible”.
2) The Tool Turning Genes On and Off
In 2013, a researcher called Stanley Qi, working currently at Stanford University, found a way to “mess up” the working of the DNA scissors, actually blunting them, and so creating a “dead” version of Cas9 that can’t cut anything at all.
The team developed ways of using the blunted enzyme to switch genes off (CRISPRi, where the i stands for interference) or on (CRISPRa, where the a stands for activation), or to tune their activity over a 1,000-fold range. They used these techniques to quickly and thoroughly screen human cells for genes that they need to grow, or to deal with a bacterial toxin.
Now, instead of a precise and versatile set of scissors, which can cut any gene you want, you have a precise and versatile delivery system, which can control any gene you want. You don’t just have an editor, but you have a tiny entity controlled from outside. It is genius and scary at the same time.
3) The Tool Treating Huntington’s Disease
One recent breakthrough is the use of a CRISPR formed from mouth bacterium that is capable of breaking RNA, the part of cells that help transform genes into usable proteins. The RNA version of CRISPR was developed by researchers at the Massachusetts Institute of Technology (MIT). It is based on a certain enzyme known as C2c2, which helps keep bacteria protected against other microbes such as viruses.
By manipulating the RNA, researchers could influence gene activity as well as the production of protein in the body. This would effectively grant them the ability to turn the process up or down, or even switch it on or off to suit their purposes without affecting the genetic codes stored in the RNA. This whole method means that it is now becoming increasingly possible to develop better forms of treatment that can target specific malignancies in the body, such as Huntington’s disease.
4) The Tool Against Malaria
The World Health Organisation (WHO) estimates that about 3.2 billion people – nearly half of the world’s population – are at risk of malaria. In 2015, there were roughly 214 million malaria cases and an estimated 438 000 malaria deaths, thus it is overtly important to fight and prevent the disease. One of the best methods is to somehow fight off its primary transmitter, infected mosquitoes.
Researchers have used gene-editing to create mosquitoes that are almost entirely resistant to the parasite that causes malaria. They used CRISPR to remove a segment of mosquito DNA, and when the mosquitoes’ genetic system tried to repair the genome, it was tricked into replacing it with a DNA construct engineered by the scientists. They found that 99 per cent of the offspring of the genetically modified insects also had the malaria-resistant genes. So some genetic change had occurred.
5) The ultimate weapon against cancer
As a very simple explanation, cancer occurs when cells refuse to die and keep multiplying in various places in our bodies, while hiding from our immune system. With CRISPR, we will have the chance to edit our cells in our immune systems to improve them against cancer cells and to help them kill these malevolent entities in time. In the future, getting rid of cancer could mean just an injection as now against mumps which was a deadly disease for children in the 1800s.
And lately, something miraculous happened. After trying traditional cancer-treating methods such as chemotherapy and bone-marrow transplants, doctors decided to use gene-editing technologies in a last-ditch effort to save a girl who was suffering from lymphoblastic leukemia. The doctors altered the immune system, namely T-cells of a donor to more effectively locate and kill leukemia cells – without attacking the patient’s organism. Actually, they did not use CRISPR, but another method, TALEN, but in any case, it turned out to be a huge success.
6) The Shield Against Duchenne Syndrome
Patients with the devastating Duchenne’s Muscular Dystrophy lose the ability to walk by their teens, and often die from one of a number of complications—like respiratory or heart failure—at a young age. The disease is caused by a mutation that prevents the body from producing the dystrophin protein, a critical protein in the development of muscle tissue.
Since the syndrome is retraceable to one specific mutation of a gene, researchers are experimenting with the use of CRISPR in finding a treatment for it. This year, experiments showed that scientists were able to treat mice with the Duchenne’s Muscular Dystrophy through gene editing – thus the technology has great promise in treating people suffering from this deadly illness in the near future.
7) With the Advancement of Research, We Could Have Clinical Trials in 2017 (!!)
The discovery of CRISPR has been having the impact on science as the discovery of the DNA and the Human Genome Project in itself was. Research labs are popping up like mushrooms, such as Intellia Therapeutics or CRISPR Therapeutics. Apparently, it is very sexy to work on CRISPR-related projects.
Editas Medicine is one of the leading genome editing, biotechnological company dedicated to treating patients with genetically-defined diseases by correcting their disease-causing genes. Its mission is to translate the promise of genome editing science into a broad class of transformative genomic medicines to benefit the greatest number of patients. Their areas of research include eye diseases, blood- muscle or lung diseases and cancer.
With the advancement of CRISPR research, it is somehow almost natural that the possibility for clinical trials appeared. Editas Medicine said that the company hopes to start a clinical trial in 2017 to treat a rare form of blindness (leber congenital amaurosis, which affects the light-receiving cells of the retina) using CRISPR. If Editas’s plans move forward, the study would likely be the first to use CRISPR to edit the DNA of a person.
These are only a few examples of the many out there. But I’m sure they will mark the beginning of a new era in genome editing and healthcare in general. However, I also believe that the long-term impacts on society and the ethics of doing research will be of much higher altitude. CRISPR could actually bring tremendous change to our future with designer babies, the eradication of diseases or that of ageing. Exactly due to such impacts, it will also generate huge ethical dilemmas and ultimate questions about our way of life.
Don’t miss the Third Part of the Article Series if You Are Curious Whether We Are About to Open Pandora’s Box Again or Rather to Get the Greatest Hope of Mankind!