A novel Dual-guide CRISPR-Cas13 strategy improves specificity for single-nucleotide variant detection

Area of Science:

• Molecular Biology
• Biotechnology
• CRISPR-Cas Systems

Background:

• CRISPR-Cas13 systems offer sensitive RNA detection via cis- and trans-cleavage.
• High sensitivity of Cas13 can lead to reduced specificity and off-target effects due to single-nucleotide mismatches.

Purpose of the Study:

• To develop an improved Cas13 system with enhanced specificity and mismatch discrimination.
• To introduce the first Dual-guide RNA system for Cas13 (dcrRNA and dtracrRNA) to enhance target recognition and reduce off-target activity.

Main Methods:

• Development of a novel Dual-guide RNA system for Cas13.
• In vitro assessment of cis- and trans-RNase activity.
• Analytical and clinical validation using SARS-CoV-2 RNA, KRAS mutations, and Leishmania sequences.

Main Results:

• The Dual-guide RNA system demonstrated robust and specific RNA cleavage.
• Accurate detection of SARS-CoV-2 RNA and differentiation of KRAS mutations (G12D vs. G12C).
• Successful differentiation of Leishmania sequence types and clinical validation confirmed accurate sample detection.

Conclusions:

• The Dual-guide Cas13 platform offers precise, rapid, and reliable RNA detection.
• This system significantly improves specificity while maintaining sensitivity for molecular diagnostics.
• The platform is a generalizable tool for next-generation diagnostics and precision RNA targeting.