概述:

In September of 2020 a new lineage of SARS-CoV-2, known as B.1.1.7 and named as Alpha variant, was discovered in the United Kingdom. This lineage developed 14 lineage-specific amino acid replacements and 3 deletions. These changes caused an increase in transmission of Alpha variant (B.1.1.7 lineage) by at least 50%, leading to increased disease severity and higher death rates. The effectiveness of COVID19 vaccines are not affected by the Alpha variant. One of the mutations associated with this lineage is a N501Y in the spike protein of the virus. It is believed that this mutation is able to increase the spike protein's affinity for the host ACE2 receptor and it has been associated with increased infectivity and virulence. B.1.1.7 viruses have also been shown to have a P681H mutation in the cleavage site of spike protein. This location is one of the residues that make up the furin proteolytic cleavage site between S1 and S2 in spike protein.

参考文献：

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