Context: In the study, scientists snipped specific genes in cultured African green monkey cells – which are susceptible to Covid-19 – and infected those gene-edited cells with Sars-CoV-2 to identify the genes that were “pro viral” or “anti viral”.
Key Points

• Using the gene-editing tool CRISPR-Cas9, scientists have traced some of the genes that either aid or stem the spread of Sars-CoV-2.

Aiding genes:

• The study confirmed that the ACE2 receptor (angiotensin-converting enzyme 2) and Cathepsin L – proteins aided the virus to cause the infection.
• The genes and pathways that assist the virus in replicating include a group of proteins that help package the DNA – called the SWI/SNF chromatin remodelling complex – and components of the TGF-β (Transforming Growth Factor- Beta).
• The study also found proteins called HMGB1, which can help activate the immune system, as pro-viral.

Deterring genes:

• The study discovered that antiviral genes such as components in histones – proteins around which the DNA winds itself to fit into a cell nucleus – deterred the virus from replicating.

Importance

• Identification of host factors essential for infection is critical to inform mechanisms of COVID-19 pathogenesis.
• The screening of such genes can help understand how the pathogen replicates in the human body.
• It can point them towards potential treatments and vaccines that can target specific genes and cellular processes to stop the virus in its tracks.