New CRISPR-Chip Finds DNA Mutations in Minutes – With No Amplification Necessary
For the first time, CRISPR-Cas9 has been combined with electronic graphene transistors to create a new handheld device which can detect specific mutations in the genome within minutes. The device, created by researchers from the University of California, the Keck Graduate Institute (KGI), Nanosens Innovations Inc and Cardea Bio Inc, can be used to quickly diagnose genetic disorders and diseases or determine the accuracy of gene-editing techniques.
This new CRISPR-Chip, as reported on in Nature journal, uses nano-electronics to find the mutations in DNA without first “amplifying” or replicating the segment of interest millions of times over through polymerase chain reaction (PCR), and as such can be used to perform genetic testing in a doctor’s office or field work setting without having to sending off samples for testing.
The new technology works by taking a deactivated Cas9 protein, which can find a specific genetic location but not cut it and attaching it to transistors made of graphene. After finding the targeted spot, the CRISPR binds to it and begins changing the graphene’s electrical conductance, thus changing the transistor’s electrical characteristics. The hand-held device developed by the researchers can then detect these changes in turn.
Kiana Aran, an assistant professor at KGI who thought up the technology idea while at Berkeley and is senior author on the paper on it in Nature, said that: “Graphene’s super-sensitivity enabled us to detect the DNA searching activities of CRISPR…CRISPR brought the selectivity, graphene transistors brought the sensitivity and, together, we were able to do this PCR-free or amplification-free detection.”
In the future, the researchers want to “multiplex” the device, allowing for the plugging in of multiple guide RNAs simultaneously to detect a number of genetic mutations at once and within minutes.
A video with more information on the CRISPR-Chip technology can be found here.