Next-generation sequencing for the genetic characterization of Maedi/Visna virus isolated from the northwest of China

Abstract

Background Maedi/Visna virus (MVV) is a contagious viral pathogen that causes considerable economic losses to the sheep industry worldwide. Objectives In China, MVV has been detected in several regions, but its molecular characteristics and genetic variations were not thoroughly investigated. Methods Therefore, in this study, we conducted next-generation sequencing on an MVV strain obtained from northwest China to reveal its genetic evolution via phylogenetic analysis. Results A MVV strain obtained from Inner Mongolia (NM) of China was identified. Sequence analysis indicated that its whole-genome length is 9193 bp. Homology comparison of nucleotides between the NM strain and reference strains showed that the sequence homology of gag and env were 77.1%–86.8% and 67.7%–75.5%, respectively. Phylogenetic analysis revealed that the NM strain was closely related to the reference strains isolated from America, which belong to the A2 type. Notably, there were 5 amino acid insertions in variable region 4 and a highly variable motif at the C-terminal of the surface glycoprotein (SU5). Conclusions The present study is the first to show the whole-genome sequence of an MVV obtained from China. The detailed analyses provide essential information for understanding the genetic characteristics of MVV, and the results enrich the MVV library.

Genetic Characterization of Small Ruminant Lentiviruses Isolated from Dairy Sheep in Greece

“…Regarding MHR, in our study, medium heterogeneity was presented among the sequences belonging to genotype A, whereas three new replacements were also observed (H/Q, N/D, and K/N). This finding is in accordance with previous studies, which reported moderate variability in the MHR of isolated strains [ 39 , 51 , 60 ]. Even though genotype A strains in our study demonstrated high similarity with the strains previously isolated in Greece, the new unique replacements that were identified could lead to a significant divergence related either to a poor diagnostic performance of serological diagnostic tools based on specific epitopes or to alternative infectivity.…”

“…Immunodominant epitopes of capsid protein have been previously characterized in many studies for the assessment of their heterogeneity [ 6 , 7 , 9 , 24 , 34 , 51 , 52 , 53 , 54 ]. Considering that immunodominant linear epitopes of capsid protein are strongly associated with the type-specific host immune response [ 46 , 53 , 55 ], their role in serological diagnosis is crucial.…”

Emergence and pandemic spread of small ruminant lentiviruses

“…Crucially, however, the basal taxa in each clade reflect SRLV diversity found near the extreme Eastern and Western ends of the Eurasian continent. Among A-like SRLVs, basal isolates are linked to regions where fat-tailed breeds have traditionally predominated and include one isolate ‘NM1111’ sampled in the Inner Mongolia region of China ( Zhao et al. 2021 ) ( Fig.…”

The genetic variability of small-ruminant lentiviruses and its impact on tropism, the development of diagnostic tests and vaccines and the effectiveness of control programmes

“…There are still limited complete genome sequences of SRLV. Therefore, it would be desirable to fully sequence the genomes using the recently developed third-generation sequencing technique to investigate recombination frequencies among SRLV ( 179 ).…”