Researchers at India’s CSIR-Institute of Genomics & Integrative Biology (CSIR-IGIB) have developed a cost-effective, CRISPR-based method to detect Helicobacter pylori (H. pylori) in rural India.
The new diagnostic test, dubbed FELUDA, will detect H. pylori and its mutations in dyspeptic patients from remote parts of India, who have limited access to diagnostic laboratories.
According to India’s Department of Science and Technology, resistance to clarithromycin is primarily attributed to point mutations in the 23S ribosomal RNA coding gene of H. pylori.
FELUDA offers a cost-effective approach to detecting H. pylori infections in human samples and identifying antibiotic resistance to facilitate its rapid eradication.
CRISPR-based methodologies enable precise recognition and cleavage of the target DNA through guide RNAs targeting respective mutation sites in various DNA sample types.
However, CRISPR-Cas9-based techniques are limited due to the requirement of NGG protospacer adjacent motif (NGG PAM) sequences while detecting mutations.
To address the limitations, researchers at CSIR-IGIB used en31-FnCas9 to detect the 23S rDNA mutation status of H. pylori in gastric biopsy samples from dyspeptic patients.
In the study, they used an engineered Cas9 protein, which resembles Cas9 orthologs, derived from Francisella novicida (en31-FnCas9) but with altered PAM binding affinity.
The study validated the potential of en31-FnCas9 to detect the 23S rDNA mutation status of H. pylori in gastric biopsy samples from dyspeptic patients of Indian origin.
It shows the significance of sequencing-free molecular diagnosis in detecting H. pylori and its antibiotic-resistance mutations to address global public health concerns.
The study showed a rapid visual readout of H. pylori infection and its mutation status in patient samples, enhancing its diagnostic potential in clinical settings.
It is the first report of en31-FnCas9 mediated molecular diagnosis of H. pylori mutations implicated in clarithromycin resistance.
Furthermore, deployment of the new methodology in a clinical setup can help enable accurate and timely reports on H. pylori antibiotic resistance, particularly in remote settings.
