Utilizing an unsuspected activity of the CRISPR-Cas12a protein, researchers created a simple diagnostic system called DETECTR to analyze cells, blood, saliva, urine and stool to detect genetic mutations, cancer and antibiotic resistance and also diagnose bacterial and viral infections. The scientists discovered that when Cas12a binds its double-stranded DNA target, it indiscriminately chews up all single-stranded DNA. They then created reporter molecules attached to single-stranded DNA to signal when Cas12a finds its target.