While CRISPR gene editing is becoming a revolutionary tool for scientists and researchers across the world, it’s not a perfect system. People working with CRISPR in a laboratory setting find that using the technique can result in editing the wrong sequences of DNA.
CRISPR in the Laboratory
The term “CRISPR” stands for Clustered Regularly Interspaced Short Palindromic Repeat. Scientists are interested in CRISPR technology to remove genes that lead to diseases or replace harmful genes with genes that are more beneficial. The technology has only been available since 2012, so much work will still go on to improve the technology.
Scientists are looking forward to using CRISPR to treat a wide range of diseases. As noted by Labiotech, the following eight disorders have the potential to be cured with CRISPR going forward:
- COVID -19: Scientists are working with CRISPR gene editing to delete genetic material used by the virus to infect people during the global pandemic.
- Cancer: Studies include using CRISPR to change immune T-cells extracted from patients and then reinfused to help the immune system defend against cancer.
- Disorders of the Blood: Sickle-cell disease and beta-thalassemia are undergoing study with CRISPR.
- Blindness: Harnessing CRISPR to address hereditary types of blindness.
- AIDS: Scientists are studying using CRISPR to remove viral DNA used by the HIV virus.
- Cystic fibrosis: Studies involve base editing to fix mutations in people’s cells without harming healthy parts of their DNA.
- Muscular dystrophy: Scientists are testing CRISPR for addressing mutations in the DMD gene.
- Huntington’s disease: Researchers hope to use CRISPR to tackle the genetic aspect of this neurodegenerative disease.
With such powerful tools at their disposal, researchers have to be concerned about CRISPR mistakenly editing the wrong genetic sequence.
Using SuperFi-Cas9 to Reduce Errors in CRISPR Gene Editing
University of Texas at Austin researchers have determined that a particular protein structure is responsible for mistakes made during CRISPR gene editing, according to a report from New Atlas. Under ordinary conditions, a scientist will employ the Cas9 protein to search for a 20-letter sequence in DNA. Sometimes, the Cas9 protein happens upon a sequence with only 18 out of 20 letters matching, and instead of ignoring the sequence, it does the edit anyway.
So the Austin scientists employed a cryo-electron microscope to visualize what Cas9 actually does when it is hunting for a sequence and edits a poorly matched set of letters in the genetic code. They found a structure shaped like a finger that stabilizes the DNA sequence under study, and it was still able to make an edit despite that only 18 out of 20 letters truly matched.
To put a stop to this incorrect editing, the researchers “tweaked” the Cas9 protein used in making edits with CRISPR. The finger no longer can stabilize a DNA sequence, reducing the occurrence of bad edits by 4,000 times, per New Atlas. This new approach to cutting down on off-target mutations in CRISPR gene editing gives scientists a more precise tool, which they have dubbed “SuperFi-Cas9.”
Tests Are Still Only Conducted in Vitro, not in Vivo
Keep in mind that this new technique using Super-Cas9 is only being done in test tubes (in vitro) rather than with live cells (in vivo).
The research team at the University of Texas in Austin do have plans to start demonstrating the use of Super-Cas9 to do CRISPR gene editing in living cells, but they have not yet announced a timetable for going forward with the next round of experiments.
Keep an Eye Out for Future Innovations
The promise of reducing errors 4,000 times using SuperFi-Cas9 is an exciting development for anyone with an interest in genetic engineering.
With any new technology, industry observers, as well as scientists working in labs and research facilities will need to keep tabs on developments that will make CRISPR easier and more effective to use. Watch this space for updates on innovations such as SuperFi-Cas9 and how they impact CRISPR gene editing.