Janice Chen is a recent PhD graduate in Molecular and Cell Biology from the University of California, Berkeley. She is the co-founder and Chief Research Officer at Mammoth Biosciences, a biotechnology company harnessing a revolutionary gene-editing tool called CRISPR – used for rapid and affordable disease detection.
CRISPR is a tool that has revolutionized the field of gene editing and is now gaining terrain outside the lab with the aim of detecting diseases through a non-invasive procedure, a revolution in its own right.
Below is the full text of her TEDx Talk titled “Could CRISPR Democratise Diagnostics?” at TEDxCERN conference.
For the past two days, you’ve been dealing with a sore throat and you just feel miserable.
Over the weekend, you develop a fever and cough and you feel too weak to even get out of bed. It’s like the worst cold you’ve ever had
You search online for a possible diagnosis and think that you might have the flu, but your symptoms also suggest a possible bacterial infection.
You decide it’s worth visiting a doctor, but because it’s the weekend, your only option is to visit the emergency services.
After an hour in the waiting room, a doctor finally examines you and sticks a swab up your nose for a flu test. She later confirms that you test positive for the flu, and sends you home with medication and instructions to rest and drink plenty of fluids.
You’re completely exhausted after the trip and hope that you didn’t spread the virus to others along the way.
What if, instead, you could directly and accurately test for the flu at home?
What if you received the prescription and treatment plan without having to step foot into a clinic? And what if the same principle could be applied to other dangerous diseases, such as Ebola or even cancer?
Today I am going to talk about a revolution in diagnostics. It involves a tool called CRISPR.
You might know CRISPR as modern genome-editing technology, but the process of CRISPR has actually existed in nature for millions of years to protect bacteria against viruses.
Bacteria, like humans, have evolved their own immune system to defend against viral infections.
Scientists eventually realized that the CRISPR immune response uses a cutting protein called Cas and an RNA molecule that guides the Cas protein to matching DNA sequence from the invading virus.
Once a Cas protein finds its target, it turns into a pair of molecular scissors small enough to fit inside a bacterium and slices apart the invader. Once it’s cut, the virus is dead and can’t harm the bacterium any longer.
In 2012, researchers from the lab of Jennifer Doudna, my former PhD adviser, were able to extract CRISPR out of bacteria and reprogram the guide RNA to target any DNA sequence. This was revolutionary.
When this kind of precision cutting is brought into a plant or animal, we can fix any faulty genes or enhance others. In short, we can rewrite the genome.
For the past six years, we’ve learned how CRISPR can help us write our genes, but today, I’m going to talk about a completely new application of CRISPR that has nothing to do with genome editing.
Last year, my colleagues and I discovered that CRISPR can also be used to help us rapidly and inexpensively read our DNA. This unexpected finding led us to reinvent CRISPR as a next-generation diagnostic.
During my time at the Doudna Lab, I wanted to understand how CRISPR proteins cut DNA. I like to imagine these tiny molecular machines made up of two macromolecules: protein and RNA.
If we zoom in further, we can break them up into their building blocks of amino acids and ribonucleotides. As a biochemist, I love being able to test this system by swapping out amino acids, tweaking ribonucleotides, and even removing entire pieces of the CRISPR protein.