Current Issues in Molecular Biology (Dec 2022)

Development and Validation of ScriptTaq COVID PCR: An In-House Multiplex rRT-PCR for Low-Cost Detection

  • Dana Abdalghani AbuObead,
  • Tasnim Khalid Alhomsi,
  • Mahmoud Zhra,
  • Bandar Alosaimi,
  • Muaawia Hamza,
  • Maaweya Awadalla,
  • Osama Ezzeldin Abdelhadi,
  • Joud Abdullah Alsharif,
  • Liliane Okdah,
  • Khaled AlKattan,
  • Saeed Al Turki,
  • Hana M. A. Fakhoury,
  • Ahmad Aljada

DOI
https://doi.org/10.3390/cimb44120417
Journal volume & issue
Vol. 44, no. 12
pp. 6117 – 6131

Abstract

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The COVID-19 pandemic necessitated an extensive testing for active SARS-CoV-2 infection. However, securing affordable diagnostic tests is a struggle for low-resource settings. We report herein the development and validation of an in-house multiplex real-time RT-PCR diagnostic test for the detection of active COVID-19 infection (ScriptTaq COVID PCR). Furthermore, we describe two methods for RNA extraction using either an in-house silica column or silica-coated magnetic beads to replace commercial RNA extraction kits. Different buffer formulations for silica column and silica-coated magnetic beads were tested and used for RNA isolation. Taq polymerase enzyme and thermostable reverse transcriptase enzyme were purified from bacterial clones. Primers/probes sequences published by the WHO and CDC were used for the qualitative detection of the RNA-dependent RNA polymerase (RdRp) and nucleocapsid (N) genes, respectively. ScriptTaq COVID PCR assay was able to detect up to 100 copies per reaction of the viral RdRP and N genes. The test demonstrated an overall agreement of 95.4%, a positive percent agreement (PPA) of 90.2%, and a negative percent agreement (NPA) of 100.0% when compared with two commercially available kits. ScriptTaq COVID PCR diagnostic test is a specific, sensitive, and low-cost alternative for low-resource settings.

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