As the number of confirmed coronavirus cases surpasses 3.7 million globally, researchers and pharmaceutical companies around the world are working under intense pressure to test samples more efficiently and develop potential vaccines as quickly as possible. To do so, many of them are using the synthetic copies of the virus that were developed in Switzerland, in the high-security laboratory of the Institute of Virology and Immunology (IVI) of the Federal Food Safety and Veterinary Office (FSVO) in Mittelhäusern and at the Vetsuisse Faculty of the University of Bern.
Being tinier than even the smallest bacteria and extremely variable, viruses are very difficult to clone. Thanks to a new method that uses yeast cells, the Swiss scientists successfully replicated the novel coronavirus within the space of a week. The results of their study have now been published in the journal Nature.
The Bern model
To clone the coronavirus, pieces of its genome were produced from synthetic DNA and then reassembled in yeast cells using a process known as transformation-associated recombination. The result was an artificial yeast chromosome on which the genetic information of the virus was stored. Infectious RNA was then produced in vitro and introduced into animal cells, where new, synthetic coronaviruses then multiplied. This method allows a rapid response to new and fast-spreading viruses.