A dual typing system establishment and global diversity analysis for sapoviruses

Area of Science:

• Virology
• Molecular Biology
• Bioinformatics

Background:

• Sapovirus, a genus within Caliciviridae, causes global gastroenteritis in humans and animals.
• Increasing viral sequences and recombinant strains necessitate refined classification criteria for Sapovirus genogroups and genotypes.

Purpose of the Study:

• To optimize the classification system for Sapoviruses.
• To establish refined criteria for Sapovirus genogroups, genotypes, types, and groups.

Main Methods:

• Evolutionary clustering and genetic distance analysis were employed.
• Classification criteria were updated by adjusting standard deviations (SD) for genetic distances.
• New criteria were established for RNA-dependent RNA polymerase (RdRp) sequences.

Main Results:

• VP1 genogroup classification was expanded to 34 genogroups, with updated genotype cutoff values (<0.161).
• New classification criteria for RdRp sequences established 24 P-groups (cutoff <0.531) and P-types (cutoff <0.266).
• Human Sapovirus classification now includes one additional genotype (GV.PNA1), three P-groups, and 21 P-types; no specific spatial-temporal distribution was observed.

Conclusions:

• A dual typing system for Sapovirus classification based on VP1 and RdRp nucleotide sequences was established.
• The refined criteria improve the accurate categorization of genetically diverse Sapovirus strains.
• This classification system provides a robust framework for future Sapovirus research and surveillance.