Genetic characterization of small ruminant lentivirus in Italian mixed flocks: evidence for a novel genotype circulating in a local goat population

Abstract

In this study, characterization of the gag gene of small ruminant lentiviruses was carried out in Italian mixed flocks. The nearly complete gag gene was amplified and sequenced. Within genotype A, subtype A1 and a novel subtype, A8, were found in goats, and another novel subtype, A9, was found in both sheep and goats. Subtype B1 was found in both host species and subtype B2 was identified only in sheep. A novel, highly divergent sequence was obtained from goats in two epidemiologically related flocks and is proposed to represent a novel genotype, E. Major epitopes of matrix and capsid antigen were highly divergent, suggesting that serological identification of animals infected with genotype E may have been missed by using currently available diagnostic tests. A recombinant subunit ELISA, based on genotype E-specific epitopes, was developed and a third independent flock carrying this genotype was identified, based on serology.

Genetic characterisation of small ruminant lentiviruses in sheep and goats from the Czech Republic

“…The output sequence data were processed in the BioEdit software (Tom Hall, 21 Table 1. Specific primers for the gag gene region designed according to Grego et al (2007 Phylogenetic analysis Obtained nucleotide sequences were analyzed, adjusted and preliminarily compared by Bio Edit software (Hall 1999). Multiple alignment of analysed sequences together with reference SRLV sequences was accomplished with Clustal W in MEGA 7 (K u m a r et al 2016).…”

“…Polymerase chain reaction Two-pair primers (Table 1) corresponding to the most highly conserved sequences in the gag gene from the targeted SRLV genomes were used for nested PCR (Grego et al 2007). The primers GAG F1 and POL R1 were used for the first PCR step, where the consequent length of the amplification product was 0.8 kb.…”

“…Rather, phylogenetic analysis on additional (gag) sequences of the same (group D) isolates, classify these sequences with genotype A, suggesting that genotype D is in fact genotype A, exhibiting divergence in the pol gene (Ramírez et al 2013). The ocurrence of genotype E is described in local goat populations in the northwestern region of Italy and the island of Sardinia (Grego 2007;Reina 2010). The high genetic variability amongst SRLV and the corresponding phylogenetic relationships amongst sequences has been described in numerous studies in different countries (Ramírez et al 2013).…”

“…The SRLV genome contains the structural genes gag, pol and env, in addition to the regulatory genes rev, vif, and tat. The gag and pol genes are relatively well conserved among SRLVs, which makes them ideal targets for Polymerase Chain Reaction (PCR) primer design (Pepin et al 1998;Grego et al 2007). The MVV prototypical strains such as strain K1514, EV-1, and SA-OMVV from sheep and the CAEV strain Cork-CAEV isolated from goat (L'Homme et al 2011) were originally viewed as distinct viral species restricted to respective host animal species.…”

Influence of chronic caprine arthritis-encephalitis virus infection on the population of peripheral blood leukocytes

“…Last years have brought the new view of their nature, revealing that they are capable of crossing the interspecies barrier not only in experimental but also natural conditions (Leroux et al 1997, Castro et al 1999, Shah et al 2004a, Pisoni et al 2005. Nowadays both these viruses are classed together as small ruminant lentiviruses (SRLV), which are further split into five groups from A to E (Shah et al 2004b, Grego et al 2007.…”