Direct sequencing of the white spot syndrome virus from Brazil: Genome assembly and new insights on phylogeny

• Published in: Virus research Vol. 245; pp. 52 - 61
• Main Authors: Dantas, Márcia Danielle A., Teixeira, Diego G., Silva-Portela, Rita Cássia B., Soares, Paulo Eduardo T., Lima, João Paulo M.S., Agnez-Lima, Lucymara F., Lanza, Daniel Carlos F.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 02.02.2018
• Subjects: Homologous regions; Recombination; Shrimp farming; WSSV; Shrimp farming; Recombination; Homologous regions; WSSV; shrimp farming; recombination; homologous regions
• ISSN: 0168-1702; 1872-7492
• DOI: 10.1016/j.virusres.2017.12.006

•The complete genome of WSSV from Brazil was assembled from direct sequencing data.•Isolates from Brazil, Mexico and Thailand have a common evolutionary origin.•Conflicting phylogenetic signals suggests recombination during the WSSV evolution.•Recent recombination events can be traced by analyzing WSSV homologous regions. White spot syndrome virus (WSSV) has been the cause of great economic losses in world shrimp farming. In this work the genome of a Brazilian WSSV isolate was determined from direct sequencing of total DNA extracted from an infected whiteleg shrimp, and assembled based on a chimera template approach. Comparisons between WSSV-BR and other isolates revealed that the Brazilian virus has a relatively small genome, and is very similar to isolates from Thailand and Mexico. A phylogenetic relationship using different approaches has demonstrated that these isolates share a common evolutionary history. An analysis of conflicting phylogenetic signals also considering genomes of other isolates revealed that the evolutionary history of WSSV may be related to recombination events. We observed that these events can also be traced at some level by analyzing the homologous regions in the WSSV genome. The existence of recombination events introduces a new point of view that must be considered in the evolutionary history of WSSV.