New Delhi:
Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST) has developed an RT-PCR kit that has a higher accuracy of detecting COVID-19 across various mutant strains, the Department of Science and Technology (DST) said on Tuesday.
The new multiplex RT-PCR kit developed by SCTIMST in Thiruvananthapuram, a DST institute, targets two SARS-CoV-2 genes — RdRp and ORFb-nsp14 — and the human RNAse P gene as the internal control to help detect a range of mutant strains.
Even though coronaviruses make far fewer errors than other RNA viruses, the mutations in S, R, and N genes often interfere with RT-PCR assay.
In order to target the multiple variants in the second wave, using two highly accurate confirmatory genes like RdRp and ORF-nsp14 can give precise results. The ORFb-nsp14 is one of the least mutated genes in COVID-19 and currently, there are no kits in the market with ORF-nsp14 as the target.
The new kit is based on multiplex Taqman chemistry, amplifying all three genes in a single reaction. The amplification time for the assay is 45 minutes, apart from the time required for the RNA isolation from nasopharyngeal swab samples.
Multiplexing two confirmatory genes will help short-list possible new variants if one of the genes fails to amplify and can be marked for sequence analysis.
The Indian Council of Medical Research (ICMR) has validated this kit at the National Institute of Virology, Pune, and found that it has 97.3 per cent sensitivity and 100 per cent specificity in COVID-19 detection.
SCTIMST has signed a non-exclusive license MoU with Huwel Lifesciences, Hyderabad, on May 14 to commercialise the kit.
“This unique RT-PCR kit will be a significant weapon in our fight against COVID-19 by a facile detection of SARS-CoV-2 mutations which are becoming increasingly important,” said DST Secretary Ashutosh Sharma.
