Is coronavirus less virulent in India? Too early to say

New Delhi (IANS) As SARS-CoV2, the new coronavirus that causes the COVID-19 disease, keeps wreaking havoc globally, a new study has come out with the finding that there may be a unique mutation in the Indian genome that needs to be studied further in detail to see if it can affect the coronavirus.

The New Delhi-based International Center for Genetic Engineering and Biotechnology (ICGEB) has performed preliminary research on SARS-CoV2 genomes from different geographical origins -- India, Italy, the US, Nepal and Wuhan in China -- to identify the notable genomic features of coronavirus.

The analysis revealed that there is only a single host microRNA (miRNA) titled "hsa-miR-27b" that is uniquely targeting the India SARS-CoV2.

"Based on our analysis, we speculate an important regulatory role of 'miR-27b' in SARS-CoV2 infection. The contradictory treatment outcomes may be due to the presence of the miR-27b target in the Indian genome specifically," said the research supported by the Department of Biotechnology (DBT), Government of India and the Indian Council of Medical Research (ICMR).

According to Dr Dinesh Gupta, lead researcher of the study published in prepreint portal bioRxiv, which is yet to be peer-reviewed, the mutations they found are not country specific but genome specific.

"The country names in this case indicate where the genome sequences are submitted from. If the mutations are in the genes that code for proteins important for binding, entry and/or replication, they may affect the survival of the virus," Gupta told IANS.

To gain further insights into host responses to viral infection, the research team predicted that antiviral host-miRNAs may be controlling the viral pathogenesis.

"Our analysis reveals nine host miRNAs which can potentially target SARS-CoV2 genes. Interestingly, the nine miRNAs do not have targets in SARS and MERS genomes. Also, 'hsa-miR-27b' is the only unique miRNA which has a target gene in the Indian SARS-CoV2 genome," the authors wrote.

However, the research has so far been done in one genome sequence from India so it is too early to predict that novel coronavirus is less virulent in the Indian context.

"The microRNAs are present in all human beings. hsa-miR-27b is one of the six antiviral microRNAs that can potentially bind to virus genes and affect its activity," said Gupta.

"In our study, which is a purely computational one, we predicted that this microRNA binds to the SARS-Cov2 genome submitted from India. However, it is too early to comment on it because there is only one high coverage sequence from India, so far," the researcher told IANS.

The total number of coronavirus positive cases in India reached 1,071 on Monday, including foreign nationals, with 942 active cases, the Union Health Ministry said.

According to the researchers, the specific genetic and miRNA spectrum should be considered as the basis of the treatment management.

The team also observed that each genome has unique mutations -- except the genome from Nepal that shares 100 per cent similarity with the Wuhan genome.

"We indeed need a detailed study on the preliminary results," said Gupta, adding that it has to be a combination of wider testing and physical distancing to help identify the infection and prevent its spread in India.