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Efficient SARS-CoV-2 Quantitative Reverse Transcriptase PCR Saliva Diagnostic Strategy utilizing Open-Source Pipetting Robots
Published on: February 11, 2022
The Y4-RNA fragment, a potential diagnostic marker, exists in saliva
Tatsuya Ishikawa1, Arisa Haino1, Mineaki Seki1
1Research Institute for Healthy Living, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Niigata 956-8603, Japan.
Abstract:
The 94-nt full-length Y4-RNA is thought to have roles in the initiation of DNA replication and RNA quality control. Although its 31/32-nt fragment also exists abundantly in plasma, little is known about its physiological role. Since the 31/32-nt Y4-RNA fragment in sera is reported to be more abundant in patients with coronary artery disease than healthy persons, the fragment may have a potential for a diagnostic and/or prognostic biomarker for some diseases regardless of its functionality. As a step toward further investigation of its potential utility, we examined if the 31/32-nt Y4-RNA fragment also exists in saliva that can be obtained noninvasively, and showed that, in addition to the 31/32-nt fragment, 14- and 11-nt Y4-RNA fragments are present in all saliva RNA samples from four healthy persons. We established a PCR method to accurately quantitate the amount of the 31/32-nt Y4-RNA fragment, and estimated its amount in saliva of healthy persons to be 0.06 ± 0.04 fmol per nanogram of saliva RNA. We also tried to develop an easier quantitation method using a DNA molecular beacon.
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