Abstract：
In the early 2000s, the global emergence of rotavirus (RVA) G12P[8] genotype was noted, while G12P[6] and G12P[9] combinations remained rare in humans. This study aimed to characterize and phylogenetically analyze three Brazilian G12P[9] and four G12P[6] RVA strains from 2011 to 2020, through RT-PCR and sequencing, in order to enhance our understanding of the genetic relationship between human and animal-origin RVA strains. G12P[6] strains displayed a DS-1-like backbone, showing a distinct genetic clustering. G12P[6] IAL-R52/2020, IAL-R95/2020 and IAL-R465/2019 strains clustered with 2019 Northeastern G12P[6] Brazilian strains and a 2018 Benin strain, whereas IAL-R86/2011 strain grouped with 2010 Northern G12P[6] 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 detected in Brazilian G12P[6] strains does not seem to be genetically linked to globally reported intergenogroup G1/G3/G9/G8P[8] DS-1-like human strains. G12P[9] strains exhibited an AU-1-like backbone with two different genotype-lineage constellations: IAL-R566/2011 and IAL-R1151/2012 belonged to a VP3/M3.V Lineage, and IAL-R870/2013 to a VP3/M3.II Lineage, suggesting two co-circulating strains in Brazil. This genetic diversity is not observed elsewhere, and the VP3/M3.II Lineage in G12P[9] strains seems to be exclusive to Brazil, indicating its evolution within the country. All three G12P[9] AU-1-like strains were closely relate to G12P[9] strains from Paraguay (2006-2007) and Brazil (2010). Phylogenetic analysis also highlighted that all South American G12P[9] AU-1-like strains had a common origin and supports 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]. Notably, certain genes 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 adds understanding to the molecular epidemiology of G12P[6] and G12P[9] RVA strains in Brazil, offering insights into their genetic diversity and evolution.
摘要：
在2000年代初期，注意到轮状病毒（RVA）G12P[8]基因型的全球出现，而G12P[6]和G12P[9]的组合在人类中仍然很少见。本研究旨在通过RT-PCR和测序对2011年至2020年的3种巴西G12P[9]和4种G12P[6]RVA菌株进行表征和系统发育分析，以增强我们对人类和动物来源RVA菌株之间遗传关系的理解。G12P[6]菌株显示出类似DS-1的骨架，显示出明显的遗传聚类。G12P[6]IAL-R52/2020，IAL-R95/2020和IAL-R465/2019菌株与2019年东北G12P[6]巴西菌株和2018年贝宁菌株聚集在一起，而IAL-R86/2011菌株与2010NorthernG12P[6]巴西菌株和来自美国和比利时的G2P[4]菌株分组。这些发现表明非洲的遗传血统和与共同传播的美国菌株共享相同的DS-1星座的重组。没有观察到最近的人畜共患重组，在巴西G12P[6]菌株中检测到的DS-1样星座似乎与全球报道的基因组间G1/G3/G9/G8P[8]DS-1样人类菌株没有遗传联系。G12P[9]菌株表现出AU-1样骨架，具有两个不同的基因型谱系星座：IAL-R566/2011和IAL-R1151/2012属于VP3/M3。V血统,和IAL-R870/2013到VP3/M3。II血统，表明巴西有两种共同传播的菌株。这种遗传多样性在其他地方没有观察到，和VP3/M3。IIG12P[9]菌株的血统似乎是巴西独有的，表明其在国内的演变。所有三种G12P[9]AU-1样菌株均与来自巴拉圭（2006-2007）和巴西（2010）的G12P[9]菌株密切相关。系统发育分析还强调，所有南美G12P[9]AU-1样菌株都有共同的起源，并支持从亚洲进口的假设。没有最近引入全球流行的G12P[9]菌株或与当地G12菌株P[8]或P[6]的重配。值得注意的是,巴西G12P[9]AU-1样菌株中的某些基因与猫/犬RVA（VP3/M3。II,NSP4/E3。IV和NSP2/N3。II),而NSP1/A3。VI可能起源于偶蹄动物，暗示了人畜共患传播的历史。这些基因组数据增加了对巴西G12P[6]和G12P[9]RVA菌株分子流行病学的理解，提供对其遗传多样性和进化的见解。
