Sherlock Holmes, Feluda... it sounds like a feast for a detective novel geek. Only, these are detections all right but of a different kind. Diagnostic tests or technologies, to be precise, to hunt down those viruses.

Late last week, the spotlight was on the Tata CRISPR test, powered by CSIR-Institute of Genomics and Integrative Biology’s (IGIB) “Feluda” or FnCas9 Editor Linked Uniform Detection Assay, when it received the Indian regulator’s approval to go commercial. The paper-based test could help in the detection of the novel coronavirus in less than an hour. And given its quality benchmarks, with 96 per cent sensitivity and 98 per cent specificity, the test evinced much interest.

CRISPR is a gene editing technology. And in this latest diagnostic application, an indigenously developed CRISPR technology is used to detect the genomic sequence of the SARS-CoV-2 virus (that causes Covid-19).

This CRISPR test is being seen as one of its kind in the world, as it used the Cas9 protein for detection applications, as compared to therapeutic use, explains Dr Anurag Agrawal, Director CSIR-IGIB.

And did the name “Feluda” follow naturally from Sherlock, for instance, also a CRISPR-based test that received `emergency use authorisation’ from the US Food and Drug Administration in May?

“It was inspired by the western Sherlock, and we decided to go with the Indian detective,” he says, adding that it does not end there. There is Jatayu (Junction for Analysis and Target Design for Your FELUDA assay), a web tool. And, no points for guessing, Feluda - the detective’s fans, there is also Topse (Feluda’s assistant), who in this case is a smartphone application (True Outcome Predicted via Strip Evaluation) “that assists Feluda”, courtesy a Chennai-based company, says Dr Debojyoti Chakraborty who, along with Dr Souvik Maiti, is co-inventor of the diagnostic test.

The Sherlock CRISPR SARS-CoV-2 kit for the detection of the virus that causes Covid-19 provides results in approximately one hour, said a note from Sherlock Biosciences, an engineering biology company focussed on making diagnostic testing better, faster and more affordable.

With Feluda, the TATA Medical and Diagnostics Ltd will set about commercialising the CRISPR test. Meanwhile, the young researchers are working on getting a point-of-care (POC) version of the test, reveals Dr Agrawal.

Chakraborty explains, “the aim is to get a simple, user-friendly, POC version that has high quality results. A POC Feluda that enables return to workplaces, for example.” But it is still research work in progress, he says, careful not to divulge any more.