A team of scientists from the Broad Institute of MIT and Harvard, the McGovern Institute for Brain Research at MIT, the Institute for Medical Engineering & Science at MIT, and the Wyss Institute for Biologically Inspired Engineering at Harvard University has adapted a CRISPR protein that targets RNA (rather than DNA) as a rapid, inexpensive, highly sensitive diagnostic tool with the potential for a transformative effect on research and global public health.

In a study published in Science, Broad institute members Feng Zhang, Jim Collins, Deb Hung, Aviv Regev, and Pardis Sabeti describe how this RNA-targeting CRISPR enzyme was harnessed as a highly sensitive detector - able to indicate the presence of as little as a single molecule of a target RNA or DNA molecule. Co-first authors Omar Abudayyeh and Jonathan Gootenberg, graduate students at MIT and Harvard, respectively, dubbed the new tool SHERLOCK (Specific High-sensitivity Enzymatic Reporter unLOCKing); this technology could one day be used to respond to viral and bacterial outbreaks, monitor antibiotic resistance, and detect cancer.

The scientists demonstrate the method's versatility on a range of applications, including:

• Detecting the presence of Zika virus in patient blood or urine samples within hours;
• Distinguishing between the genetic sequences of African and American strains of Zika virus;
• Discriminating specific types of bacteria, such as E. coli;
• Detecting antibiotic resistance genes;
• Identifying cancerous mutations in simulated cell-free DNA fragments; and
• Rapidly reading human genetic information, such as risk of heart disease, from a saliva sample.

Because the tool can be designed for use as a paper-based test that does not require refrigeration, the researchers say it is well suited for fast deployment and widespread use inside and outside of traditional settings -- such as at a field hospital during an outbreak, or a rural clinic with limited access to advanced equipment.