Amplification Refractory Mutation System (ARMS)-PCR for Waxy Sorghum Authentication with Single-Nucleotide Resolution

Rapid Genotyping of FecB Mutation in Sheep Using CRISPR-Cas12a Integrated with DNA Nanotree Biosensing Platform

The A-to-G mutation (FecB) in the BMPR1B gene is strongly linked to fertility in sheep, significantly increasing ovulation rates and litter sizes compared to wild-type populations. The rapid and reliable screening of the FecB gene is therefore critical for advancing sheep breeding programs. This study aimed to develop a fast and accurate method for detecting the FecB mutation and genotyping the gene to enhance sheep reproduction and productivity. To achieve this, we integrated the CRISPR-Cas12a system with an optimized amplification refractory mutation system (ARMS). A similar DNA origami technique-based fluorescence reporter nanotree structure was synthesized using gold nanomagnetic beads as carriers to amplify the fluorescence signal further. The resulting biosensing platform, termed CRISPR-ARMS, demonstrated excellent sensitivity for detecting FecB mutations, with a detection limit as low as 0.02 pmol. Therefore, this innovative approach shows great promise for single-base mutation detection and represents a pioneering tool for high-yield genetic screening.

Sensitive Detection of a Single-Nucleotide Polymorphism in Foodborne Pathogens Using CRISPR/Cas12a-Signaling ARMS-PCR

Salmonella infection, particularly that caused by drug-resistant strain, has become a worldwide public health issue. Herein, we presented a CRISPR/Cas12a-signaling ARMS-PCR assay, termed cARMS, capable of sensitively detecting drug-resistant Salmonella enterica (S. enterica) involving single-nucleotide polymorphism (SNP). Owing to the dual-recognition processes, i.e., allele-specific primed polymerization and CRISPR/Cas12 binding, the cARMS assay yielded a high sensitivity for detecting SNP down to ∼0.5%. We used the cARMS assay to investigate the adaptation of SNP-involved drug-resistant S. enterica to salt stress. It was found that the mutants exhibited stronger adaptation to salt stress, indicating the potential risk of using high salt content as a sterilization strategy. The results verified the feasibility of the cARMS assay in controlling SNP-involved bacteria-associated biosafety.