CRISPR in Medicine.
CRISPR is a gene editing tool.
It is now being used to diagnose the presence of cancer, and to create tests for infections,
like the Zika virus.
CRISPR-cas9 was first described in 2012.
It gives scientists the genetic equivalent of a word processor cursor.
It allows them to home in on specific parts of a genome,
to delete, insert, copy, cut, and paste DNA.
Scientist modified the CRISPR system,
so that it recognised the product produced by the genes.
They used CRISPR to recognise specific substances that bacteria and viruses make.
Picking up even the slightest trace of these products,
can alert doctors that an infection is active.
The system was called SHERLOCK, and could accurately distinguish between the Zika virus,
and dengue virus from blood, urine, and saliva samples.
SHERLOCK could provide the test results more quickly than current tests.
Current tests take days to culture microbes like bacteria and viruses to confirm results.
SHERLOCK could identify a bacteria or virus in less than an hour.
SHERLOCK also provided a way to measure how much virus was there.
This gives doctors a better sense of how entrenched the infection could be.
SHERLOCK could also pickup mutations present in tumours from blood.
The technology could be critical in the fight against bacteria resistance.
SHERLOCK could determine if a person’s bacterial infection,
is already resistance to certain antibiotics.
It could also pickup when a person’s infections starts to become resistant to the drug.
This will help doctors switch to a different antibiotic if when required.
The technology has the potential to be developed as a point of care diagnostic tool,
which is as easy to use, as a home pregnancy test.
The CRISPR system requires a kit designed to recognise the bacteria,
virus or cancer mutation.
The tests are reasonably inexpensive.
A typical test could cost less than a dollar.
This could help low income countries, to contain the spread of infectious diseases.