A-259 Detecting Human RNase P Gene Prevents False-Negative of SARS-CoV-2

Abstract

Abstract Background Real-time Reverse transcriptase—polymerase chain reaction (RT-PCR) is a regular technique for detecting SARS-CoV-2 infection. Human RNase P sequence is using as internal control for PCR assay usually. This article discusses the correlation between SARS-CoV-2 PCR result and human RNase P gene result. Methods Nasopharyngeal swabs were collected from two patients within three consecutive days. We detected for SARS-CoV-2 target gene and human RNase P gene by using real-time RT-PCR assay, which SARS-CoV-2 target gene includes E gene, Rarp gene and N gene . And the threshold cycle values (Ct) were determined by cobas® z 480. Evaluate the results of SARS-CoV-2 and RNase P gene detection. All samples were also analysis for SARS-CoV-2 infection in Taiwan Centers for Disease Control. Results Results of SARS-CoV-2 PCR assay were consistent in both laboratories. SARS-CoV-2 target genes were detected from specimens of both patients on day1. Ct values of E gene were 29.63 and 29.50. Ct values of Rdrp gene were 32.23 and 32.50. Ct values of N gene were 33.09 and 32.68. Ct values of RNase P gene were 21.21 and 21.22. On day 2 and 3, all specimens were negative detected for SARS-CoV-2 PCR. Ct values of RNase P gene were 25.73 and 26.16 on day 2 and 29.82 and 30.28 on day 3. Conclusion The Ct values of human RNase P gene detection can be correlated with the numbers of collected cells. Comparing the results of two patients for three consecutive days, the Ct value of human RNase P gene related to SARS-CoV-2 PCR result. Collection technique can be a factor to affect Ct value of human RNase P gene detection. Develop acceptance range for Ct value of RNase P gene detection can be a quality standard for sample collection to prevent false-negative of SARS-CoV-2.