NEW YORK : Scientists have identified a pattern of mutations in the novel coronavirus which enable it to evade the immune system's antibodies, findings that shed light on how the virus may possibly escape existing vaccines and therapeutics.According to the researchers, including those from the University of Pittsburgh in the US, the coronavirus undergoes selective deletions in parts of its genetic sequence that encode for the shape of its spike protein.The spike protein is the part of the coronavirus which enables it to infect host cells, and is also the segment of the virus against which the body produces neutralising antibodies.The study, published in the journal Science, assessed nearly 1,50,000 gene sequences of the spike protein.