Dados do Trabalho

Título

The Evolution and Genetic Diversity of G12P[6] DS-1-like and G12P[9] AU-1-like Rotavirus Variants in Brazil

Introdução

In the early 2000s, the global emergence of rotavirus A (RVA) G12P[8] genotype was noted, while G12P[6] and G12P[9] combinations remained rare in humans.

Objetivo (s)

This study aimed to genetically analyze three Brazilian G12P[9] and four G12P[6] strains from 2011 to 2020, enhancing our understanding of the genetic relationship between human and animal-origin RVA strains.

Material e Métodos

Brazilian G12P[9] and G12P[6] strains were obtained through RT-PCR and Sanger sequencing, followed by phylogenetic analyses alongside global RVA strains.

Resultados e Conclusão

G12P[6] strains showed a DS-1-like backbone, forming distinct genetic clusters. Specifically, strains IAL-R52/2020, IAL-R95/2020, and IAL-R465/2019 clustered with 2019 Northeastern Brazilian strains and a 2018 Benin strain. In contrast, strain IAL-R86/2011 grouped with 2010 Northern Brazilian strains and G2P[4] strains from the United States and Belgium. These findings suggest an African genetic ancestry and reassortments with co-circulating American strains sharing the same DS-1-like constellation. No recent zoonotic reassortment was observed and the DS-1-like constellation in Brazilian G12P[6] strains does not appear to be genetically linked to globally reported intergenogroup G1/G3/G9/G8P[8] DS-1-like human strains. In contrast, G12P[9] strains displayed an AU-1-like backbone with two distinct genotype-lineage constellations: strains IAL-R566/2011 and IAL-R1151/2012 belonged to a VP3/M3.V Lineage, while strain IAL-R870/2013 belonged to a VP3/M3.II Lineage, indicating two co-circulating strains in Brazil. This genetic diversity is unique, with the VP3/M3.II Lineage in G12P[9] strains seemingly exclusive to Brazil, suggesting its evolution within the country. All three G12P[9] AU-1-like strains were closely related to G12P[9] strains from Paraguay (2006-2007) and Brazil (2010). Phylogenetic analysis highlighted a common origin for all South American G12P[9] AU-1-like strains, supporting the hypothesis of their importation from Asia, with no recent introduction from globally circulating G12P[9] strains or reassortments with local G12 strains P[8] or P[6]. Additionally, segments in the Brazilian G12P[9] AU-1-like strains share ancestry with feline/canine RVAs (VP3/M3.II, NSP4/E3.IV, and NSP2/N3.II), whereas NSP1/A3.VI likely originated from artiodactyls, suggesting a history of zoonotic transmission with human strains. This genomic data sheds light on the genetic diversity and evolution of G12 strains.

Palavras Chave

Genetic diversity; Zoonotic transmission; Rotavirus; Genotype-lineage constellations