Daijiworld Media Network - New Delhi
New Delhi, Mar 17: A team of researchers has developed an advanced gene-based diagnostic technology that enables rapid and highly sensitive detection of multi-drug-resistant bacteria and other pathogens, even at extremely low concentrations.
The groundbreaking research, published in the Proceedings of the National Academy of Sciences (PNAS), introduces a CRISPR-based testing system that eliminates the need for nucleic acid amplification—a key limitation in traditional diagnostic methods.
The study was led by Professor Rashid Bashir from the University of Illinois Grainger College of Engineering, who, along with his team, designed a novel CRISPR-Cascade system for highly efficient pathogen detection.
In conventional CRISPR/Cas-based diagnostics, a guide RNA binds to pathogen-specific DNA or RNA, activating Cas enzymes to cleave reporter nucleic acids, which then fluoresce upon cleavage. However, a single CRISPR-based approach often struggles to detect low-level pathogens without an amplification step.
To overcome this, Bashir’s team developed a dual CRISPR-Cascade system, which significantly enhances detection sensitivity. The first CRISPR/Cas unit identifies and cleaves pathogen DNA. This activates a secondary CRISPR/Cas complex, triggering a positive feedback loop that amplifies the detection signal without additional processing.
This novel CRISPR-Cascade approach demonstrated exceptional detection capability. It successfully identified multi-drug-resistant Staphylococcus aureus (MRSA) DNA at concentrations far below the limits of existing single-Cas tests—without requiring pre-amplification.
The test delivers a simple "yes/no" result, effectively detecting specific pathogens in samples containing multiple bloodstream infections.
The researchers believe this advancement could pave the way for next-generation CRISPR-based diagnostic tools that provide real-time pathogen detection within minutes—offering a crucial breakthrough for early disease diagnosis and effective infection control.