Comparative Analysis of Emerging B.1.1.7+E484K SARS-CoV-2 Isolates

Area of Science:

• Virology
• Genomics
• Epidemiology

Background:

• The emergence of SARS-CoV-2 variants with concerning mutations, such as E484K, necessitates genomic surveillance.
• The B.1.1.7 lineage, known for increased transmissibility, combined with the E484K mutation, poses a significant public health threat.

Purpose of the Study:

• To report the genome of a B.1.1.7+E484K SARS-CoV-2 strain from Southeastern Pennsylvania.
• To compare this genome with other high-coverage B.1.1.7+E484K genomes globally to understand its evolutionary landscape within the United States.

Main Methods:

• Whole-genome sequencing of the SARS-CoV-2 B.1.1.7+E484K variant.
• Bioinformatic analysis and comparison with a dataset of 235 high-coverage B.1.1.7+E484K genomes.

Main Results:

• Identification and characterization of a novel B.1.1.7+E484K SARS-CoV-2 genome from Pennsylvania.
• Analysis revealed the presence of at least four distinct clades of this variant circulating within the United States.
• Evidence suggests at least 59 independent instances of the E484K mutation acquisition within the B.1.1.7 lineage.

Conclusions:

• The B.1.1.7+E484K variant is evolving and diversifying within the U.S., with multiple clades and independent mutation events.
• Genomic surveillance is crucial for tracking the spread and evolution of SARS-CoV-2 variants.
• Understanding the independent acquisition of mutations like E484K is vital for predicting variant behavior and informing public health strategies.