What should have been a yearlong project has turned into a race against time to stop the SARS-CoV-2 pandemic. In fifteen days, the Liver Diseases research group of the Vall d'Hebron Research Institute (VHIR) with extensive experience in mass sequencing techniques, and the Respiratory Virus Unit of the Microbiology Service of the Vall d'Hebron University Hospital, have sequenced the complete genome of two strains of SARS-CoV-2 from two patients.

These are two complete and error-free sequences that can already be consulted in GISAID, an international, freely accessible database that collects the sequences of thousands of influenza viruses and which now also includes SARS-CoV-2, as well as related epidemiological and clinical data.

In record time and only with their own resources, they have been able to develop the massive sequencing methodology to obtain the complete genome of the virus and from now on be able to do it in more patients.

And this achievement, which would not have been possible without all the work carried out for years with the hepatitis C virus in Vall d'Hebron, will help to know why there are patients who respond better or worse to the virus. In other words, it will be possible to know for each patient, individually, how the virus is influencing the development of the disease.

Dr. Tomás Pumarola, head of the Vall d'Hebron Microbiology Service, comments that the work has been the result of close collaboration between Dr. Andrés Anton, head of the Respiratory Virus Unit of the Microbiology Service of the University Hospital Vall d'Hebron, where Dr. Maria Gema Codina and researchers Cristina Cristina, María Piñana and Ariadna Rando have also collaborated; and Dr. Josep Quer, Principal Investigator and Head of Hepatitis C Virus Research, from the Liver Disease Research Group of the Vall d'Hebron Research Institute, where two other researchers, Damir Garcia-cehic and Mercedes Guerrero, have also collaborated.

Why is sequencing the entire virus so important?

From an epidemiological point of view, it allows to compare the sequences between different populations and countries around the world to see how the virus changes as it spreads among the population. This knowledge will be useful to predict what may happen in the coming years and how to act.

Obtaining the complete SARS-CoV-2 virus genome in each individual opens the doors to the study of its variability, virus evolution, and patient prognostic factors.

Also, studying these sequences we can study the degree of conservation, that is, we can see which are the areas of the virus that almost never change and therefore would be the best targets for the design of direct-acting vaccines and antivirals.