A Comprehensive Genomic Investigation of Mumps Virus Genotype G Isolates from Dibrugarh, Assam: Insights from Whole...

Mumps, caused by Mumps virus (MuV) in the Paramyxoviridae family, features a 15,384 nucleotide RNA genome. Despite vaccination efforts, mumps outbreaks persist, particularly in regions with optional vaccination policies like India. Therefore, this study aims to understand genomic variations of the complete genome of MuV genotype G from Assam, India as these genetic changes is essential for evaluating vaccine effectiveness and devising strategies against the evolving pathogen. Whole genome sequencing (WGS) was performed on two samples from 2016 and 2017. The genomes were annotated using the WHO reference genome (genotype G) and compared with vaccine strains (Jeryl Lynn and L Zagreb,) and other Indian MuV genotype G complete genome sequences. Phylogenetic analysis, N-glycosylation site determination, and epitope conservancy analysis were conducted. Structural variations were assessed using 3D models. The genomes of Assam MuV (G1 and G2) were 15,305 bp and 15,377 bp, respectively. Genome sequencing reveals unique genetic variations in various coding genes, notably in nucleoprotein, phosphoprotein, matrix, and fusion. These variations include substitutions exclusive to Assam sequences, indicating antigenic site involvement. The HN protein analysis points to potential vaccine escape mutants with substitutions at positions 279 and 287. A structural assessment demonstrates no significant alterations in overall secondary conformation, but a noteworthy substitution in B-cell epitopic region (N323K) raises concerns about immune evasion. The identified genetic variations suggest evolving antigenicity in MuV genotype G, which may impact vaccine effectiveness. Continuous genomic surveillance and immunological studies are crucial for optimizing vaccination strategies and addressing the evolving pathogen.

The online version contains supplementary material available at 10.1007/s12088-025-01489-6.