Genome sequencing expert claims this but doubts methods of sample collection adopted by authorities in Maharashtra; other specialists say sample size too small
A health worker handles swab samples at the laboratory of the jumbo COVID centre at BKC. File pic/Atul Kamble
A double mutation has been detected in 61 per cent of the total 361 COVID-19 samples tested between January and March this year, a genome sequencing expert claimed on Wednesday even as he raised doubts over the methods of sample collection being adopted by authorities in Maharashtra, which is worst affected by the pandemic.
ADVERTISEMENT
However, experts in genome sequencing and cell science said that such a small sample cannot be considered an indication of the spread of the mutated virus. These 361 samples were tested at the genome sequencing laboratories in Maharashtra.
“I am told that out of 361 COVID-19 samples tested by the National Institute of Virology in Pune, 61 per cent had the double mutation. However, this sample size is too small to conclude as Maharashtra has been conducting nearly two lakh tests per day, ” a senior genome sequencing expert said.
Stressing that the sample collection has to be random, he said the double mutation was found in all samples from a particular set of 10 from Nashik.
This means that these samples could be from a big joint family. “Another possibility is that the people could be from the same area. (sample collection done this way) completely defeats the purpose of random sampling and the genome sequencing efforts,” the expert added. Genome sequencing is the process of determining the entirety, or nearly the entirety, of the DNA sequence of an organism’s genome at a single time.
‘No word from labs’
BMC Additional Commissioner Suresh Kakani said that samples are regularly sent to genome sequencing laboratories, but there is no communication from them. “We still do not know whether the samples contain the double mutation of the novel Coronavirus or whether it is the earlier variant. If genome sequencing identifies the presence of double mutant virus (technically known as B.1.617) in the samples, we can issue revised guidelines to minimise its spread as it is more infectious,” Kakani said.
He said the need of the hour is a regular update from the Centre or the consortium of ten laboratories set up for genome sequencing (by the Union government). Known as the Indian SARS-CoV-2 Consortium on Genomics (INSACOG), it has identified two important mutations dubbed as a double mutant. The double mutant has been reported in various countries.
“Unless the communication is smooth, it will take a longer time for the state machinery to know whether they are dealing with an old variant of COVID-19 or an infectious one. We are lucky that the virus is not mutated yet and not become lethal. We cannot afford to learn about the status of the virus so late due to the lack of communication between these laboratories,” another scientist said.