Journal of Clinical and Biomedical Sciences
DOI: 10.58739/jcbs/v16i2.25.311
Year: 2026, Volume: 16, Issue: 2, Pages: 31-35
Original Article
Prabhjot Kaur Gill1*, Amandeep Singh2
1Professor, Centre for Advanced Research and Development (Genetics, SGRDIMSR), Sri Guru Ram Das University of Health Sciences, Sri Amritsar, 143501, Punjab, India.
2Ph.D. Scholar, Centre for Interdisciplinary Biomedical Research, Adesh University, Bathinda, Punjab, India.
*Corresponding Author
Email: [email protected]
Received Date:04 August 2025, Accepted Date:27 April 2025, Published Date:15 June 2026
Objectives: The present study focused on the molecular identification and evaluation of specific gene targets for the rapid and accurate detection of Salmonella typhi from blood samples of patients diagnosed with typhoid fever. Methodology: Three representative isolates were subjected to 16S rRNA gene sequencing, and their identity as S. typhi was confirmed via BLASTn analysis with 100% sequence identity and query coverage. To develop a DNA-based diagnostic tool, single gene-target PCR assays were optimized using six primer sets targeting STY2020, STY2021, STY0201, STY0307, STY0322, and STY0326. Results: Five of these assays successfully identified all S. typhi isolates with 100% sensitivity and specificity, while the STY0322 assay failed to amplify any strains. Detection limit analysis using serially diluted genomic DNA revealed that STY0307 was the most sensitive target (5.0 pg), followed by STY0201 and STY2021 (10 pg). Lower sensitivity was observed with STY2020 and STY0326 (50 pg), with only faint gel electrophoresis bands. These results indicate that STY0307, STY0201, and STY2021 are highly reliable markers for S. typhi detection. Furthermore, low expression levels of STY2020 and STY0326 during infection underscore the need for further population-based studies. Conclusion: STY0307 and STY2021 emerged as the most promising gene targets for diagnostic purposes and could be leveraged for the development of low-cost, rapid, and accurate point-of-care diagnostics suitable for use in resource-limited settings.
Keywords: Diagnostic tool, Gene-specific markers, PCR assay, Salmonella typhi, Typhoid fever
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Published By Sri Devaraj Urs Academy of Higher Education, Kolar, Karnataka
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