Table 1 Pros and cons of CRISPR-based assay for infectious disease. Adapted from James P. Broughton  et. al., 2020, Nature biotechnology, CRISPR–Cas12-based detection of SARS-CoV-2

Target

E gene and N gene^a

N gene (three amplicons, N1, N2 and N3)

Sample control

RNase P

RNase P

LoD

10 copies per μl input

1 copy per μl input^b and 3.2 copies per μl input^c

Assay reaction time (approximate)

30–40 min

120 min

Assay sample-to-result time (approximate)

45 min (with manual RNA extraction)

4 h (including RNA extraction)

Assay results

Qualitative

Quantitative

Assay components

RT–LAMP (62 °C, 20–30 min) Cas12

(37 °C, 10 min) Lateral flow strip (RT, 2 min; no additional time if using

fluorescence readout)

UDG digestion (25 °C, 2 min), reverse transcription (50 °C, 15 min), denature (95 °C, 2 min) amplification, (95 °C, 3 s; 55 °C 30 s; 45 cycles)

Bulky instrumentation

required

No

Yes

US FDA EUA approval

Pending clinical validation

Yes