Colorimetric detection of SARS-CoV-2 by uracil-DNA glycosylase (UDG) reverse transcription loop-mediated isothermal amplification (RT-LAMP)

Int J Infect Dis. 2022 Jul:120:132-134. doi: 10.1016/j.ijid.2022.04.036. Epub 2022 Apr 25.

Abstract

Objectives: Preventing reverse transcription loop-mediated isothermal amplification (RT-LAMP) carryover contamination could be solved by adding deoxyuridine triphosphate (dUTP) and uracil-DNA glycosylase (UDG) into the reaction master mix.

Methods: RNA was extracted from nasopharyngeal swab samples by a simple RNA extraction method.

Results: Testing of 77 samples demonstrated 91.2% sensitivity (95% confidence interval [CI]: 78-98.2%) and 100% specificity (95% confidence interval: 92-100%) using UDG RT-LAMP.

Conclusion: This colorimetric UDG RT-LAMP is a simple-to-use, fast, and easy-to-interpret method, which could serve as an alternative for diagnosis of SARS-CoV-2 infection, especially in remote hospitals and laboratories with under-equipped medical facilities.

Keywords: Carryover contamination; RT-LAMP; SARS-CoV-2; UDG; dUTP.

MeSH terms

  • COVID-19* / diagnosis
  • Colorimetry
  • Humans
  • Molecular Diagnostic Techniques / methods
  • Nucleic Acid Amplification Techniques / methods
  • RNA
  • RNA, Viral / genetics
  • Reverse Transcription
  • SARS-CoV-2* / genetics
  • Sensitivity and Specificity
  • Uracil-DNA Glycosidase / genetics
  • Uracil-DNA Glycosidase / metabolism

Substances

  • RNA, Viral
  • RNA
  • Uracil-DNA Glycosidase

Supplementary concepts

  • LAMP assay