Recurrent emergence of SARS-CoV-2 spike deletion H69/V70 and its role in the Alpha variant B.1.1.7
Publication: Cell Reports
Bo Meng, Steven A. Kemp, Guido Papa, Rawlings Datir, Isabella A.T.M. Ferreira, Sara Marelli, William T. Harvey, Spyros Lytras, Ahmed Mohamed, Giulia Gallo, Nazia Thakur, Dami A. Collier, Petra Mlcochova
29 June 2021
One of the key mutations seen in the ‘Alpha variant’ of SARS-CoV-2 – the deletion of two amino acids, H69/V70 – enables the virus to overcome chinks in its armour as it evolves, say an international team of scientists.
SARS-CoV-2 is a coronavirus, so named because spike proteins on its surface give it the appearance of a crown (‘corona’). The spike proteins bind to ACE2, a protein receptor found on the surface of cells in our body. Both the spike protein and ACE2 are then cleaved, allowing genetic material from the virus to enter the host cell. The virus manipulates the host cell’s machinery to allow the virus to replicate and spread.
As SARS-CoV-2 divides and replicates, errors in its genetic makeup cause it to mutate. Some mutations make the virus more transmissible or more infectious, some help it evade the immune response, potentially making vaccines less effective, while others have little effect.
Towards the end of 2020, Cambridge scientists observed SARS-CoV-2 mutating in the case of an immunocompromised patient treated with convalescent plasma. In particular, they saw the emergence of a key mutation – the deletion of two amino acids, H69/V70, in the spike protein. This deletion was later found in B1.1.7, the variant that led to the UK being forced once again into strict lockdown in December (now referred to as the ‘Alpha variant’).
Researchers led by scientists at the University of Cambridge show that the deletion H69/V70 is present in more than 600,000 SARS-CoV-2 genome sequences worldwide, and has seen global expansion, particularly across much of Europe, Africa and Asia.
- Read the press release about this research.