Emergence of Lineage E.4 and Structural Plasticity of A28L Protein in Mpox Virus: Characterization of LCR7 Length Polymorphisms Across Lineages — Shenzhen City, Guangdong Province, China, 2023–2025
TL;DR
Structural variation in A28L provides additional insight into MPXV evolution beyond conventional single-nucleotide analyses, and continued surveillance of these genomic features may improve monitoring of viral transmission and the emergence of new variants.
Abstract
What is already known about this topic? The A28L protein is involved in mpox virus (MPXV) attachment and fusion, is a major target of neutralizing antibodies, and contains regions prone to genetic variation. What is added by this report? Analysis of 6,834 global and 260 Shenzhen MPXV genomes identified lineage-specific length polymorphisms in the A28L low-complexity region (LCR7). Emerging E.4 viruses exhibited complex deletion patterns and a characteristic OPG153_E293Q substitution, indicating ongoing structural diversification. What are the implications for public health practice? Structural variation in A28L provides additional insight into MPXV evolution beyond conventional single-nucleotide analyses. Continued surveillance of these genomic features may improve monitoring of viral transmission and the emergence of new variants.