Search results for "reassortment"
showing 10 items of 16 documents
Population Genomics of Human Viruses
2018
Viruses, and a few RNA viruses in particular, represent one of the greatest threats for human health. High mutation rates, large population sizes, and short generation times contribute to their typically fast evolutionary rates. However, many additional processes operate on their genomes, often in opposite directions, driving their evolution and allowing them to adapt to diverse host populations and antiviral drugs. Until recently, the high levels of genetic variation of most viruses have been explored only at a few genes or genome regions. The recent advent and increasing affordability of next-generation sequencing techniques have allowed obtaining complete genome sequences of large number…
Rotavirus genotypes co-circulating in Europe between 2006 and 2009 as determined by EuroRotaNet, a pan-European collaborative strain surveillance net…
2011
SUMMARYEuroRotaNet, a laboratory network, was established in order to determine the diversity of co-circulating rotavirus strains in Europe over three or more rotavirus seasons from 2006/2007 and currently includes 16 countries. This report highlights the tremendous diversity of rotavirus strains co-circulating in the European population during three years of surveillance since 2006/2007 and points to the possible origins of these strains including genetic reassortment and interspecies transmission. Furthermore, the ability of the network to identify strains circulating with an incidence of ⩾1% allowed the identification of possible emerging strains such as G8 and G12 since the beginning of…
Unusual Assortment of Segments in 2 Rare Human Rotavirus Genomes
2010
Using full-length genome sequence analysis, we investigated 2 rare G3P[9] human rotavirus strains isolated from children with diarrhea. The genomes were recognized as assortments of genes closely related to rotaviruses originating from cats, ruminants, and humans. Results suggest multiple transmissions of genes from animal to human strains of rotaviruses.
Molecular characterization of rotavirus strains from children with diarrhea in Italy, 2007-2009.
2011
The surveillance network RotaNet-Italia was established in 2007 in order to investigate the diversity of co-circulating rotavirus strains in Italy, and to provide a baseline for future assessment of possible effects of vaccine implementation in selecting novel versus common rotavirus strains. A total of 2,645 rotavirus strains from pediatric patients with acute diarrhea were collected over three consecutive seasons from September 2006 through August 2009, and partially characterized by standardized multiplex RT-PCR. Most of strains (89.1%) belonged to genotypes G1–G4, and G9, associated with either P[8] or P[4], commonly found in humans worldwide. However, in at least 2.0% of cases, viruses…
Sexual selection and intelligence: Does sexual reproduction drive the evolution of intelligence?
2009
Abstract The basal hypothesis discussed here is the idea that brain architecture could be plastic on a very basal, genetic level due to sexual recombination and reassortment of alleles of genes related to brain development, e.g., neuronal cell adhesion molecules (NCAMs) and others. The role of sexual reassortment leads the study of brain development, species behavior and intelligence to a new version of the so-called “Red Queen Hypothesis”: using the mechanism described here, a kind of runaway selection mechanism seems to arise. Even if NCAMs are almost constant within an individual, they seem to act very differently at the population level and so the role of reassorting polymorphic NCAM- (…
Presence of viruses in wild eels Anguilla anguilla L, from the Albufera Lake (Spain)
2014
A virological analysis was conducted on wild eels from the Albufera Lake (Spain). A total of 179 individuals at different growth stages were collected in two different surveys (2004 and 2008). Presence of anguillid herpesvirus (AngHV-1), aquabirnavirus and betanodavirus was confirmed by PCR procedures in both surveys, although the number of detections was clearly higher in 2008 (83% of the eels analysed resulted positive for virus presence). AngHV-1 was the viral agent most frequently detected, followed by aquabirnaviruses. Betanodaviruses were detected by the first time in wild eels, and although the detections were only made by nested PCR, high percentage of positives were achieved. In ad…
Rare AU-1-like G3P[9] human rotaviruses with a Kun-like NSP4 gene in children with diarrhea in Italy
2007
ABSTRACT Three G3P[9] rotaviruses, detected in children hospitalized with gastroenteritis in Palermo, Italy, were found to be genetically related to strains of either human or feline origin in the VP7, VP4, and VP6 genes. In contrast, in the NSP4 gene the viruses resembled G2P[4] human strains, suggesting a reassortment between AU-1-like and Kun-like strains.
Recombination in viruses: Mechanisms, methods of study, and evolutionary consequences
2014
© 2014 Elsevier B.V. Recombination is a pervasive process generating diversity in most viruses. It joins variants that arise independently within the same molecule, creating new opportunities for viruses to overcome selective pressures and to adapt to new environments and hosts. Consequently, the analysis of viral recombination attracts the interest of clinicians, epidemiologists, molecular biologists and evolutionary biologists. In this review we present an overview of three major areas related to viral recombination: (i) the molecular mechanisms that underlie recombination in model viruses, including DNA-viruses (Herpesvirus) and RNA-viruses (Human Influenza Virus and Human Immunodeficien…
Identification of a multi-reassortant G12P[9] rotavirus with novel VP1, VP2, VP3 and NSP2 genotypes in a child with acute gastroenteritis.
2015
The G12 rotavirus genotype is globally emerging to cause severe gastroenteritis in children. Common G12 rotaviruses have either a Wa-like or DS-1-like genome constellation, while some G12 strains may have unusual genome composition. In this study, we determined the full-genome sequence of a G12P[9] strain (ME848/12) detected in a child hospitalized with acute gastroenteritis in Italy in 2012. Strain ME848/12 showed a complex genetic constellation (G12-P[9]-I17-R12-C12-M11-A12-N12-T7-E6-H2), likely derived from multiple reassortment events, with the VP1, VP2, VP3 and NSP2 genes being established as novel genotypes R12, C12, M11 and N12, respectively. Gathering sequence data on human and anim…
Multiple reassortment and interspecies transmission events contribute to the diversity of feline, canine and feline/canine-like human group A rotavir…
2011
Abstract RNA–RNA hybridization assays and complete genome sequence analyses have shown that feline rotavirus (FRV) and canine rotavirus (CRV) strains display at least two distinct genotype constellations (genogroups), represented by the FRV strain RVA/Cat-tc/AUS/Cat97/1984/G3P[3] and the human rotavirus (HRV) strain RVA/Human-tc/JPN/AU-1/1982/G3P3[9], respectively. G3P[3] and G3P[9] strains have been detected sporadically in humans. The complete genomes of two CRV strains (RVA/Dog-tc/ITA/RV198-95/1995/G3P[3] and RVA/Dog-tc/ITA/RV52-96/1996/G3P[3]) and an unusual HRV strain (RVA/Human-tc/ITA/PA260-97/1997/G3P[3]) were determined to further elucidate the complex relationships among FRV, CRV a…