Full genome analysis of a novel genotype of Decapod hepandensovirus 1 (DHPV) infecting Pacific whiteleg shrimp, Penaeus vannamei

Abstract

Decapod hepandensovirus 1 (DHPV) is a viral pathogen that causes growth retardation and decreased feed conversion efficiency in penaeid shrimp. The virus exhibits high genetic variation between different hosts and geographical locations. It has been primarily reported in cultured Penaeus monodon, P. chinensis, and P. merguiensis, and a new type of DHPV has recently been reported in P. vannamei cultured in Korea and Taiwan. In this study, the genome of a recently reported new type of DHPV was fully sequenced by conventional Sanger sequencing combined with a next-generation sequencing approach. Similar to the other types of DHPVs infecting several shrimp species other than P. vannamei, a new type of DHPV contained a linear, single-stranded DNA genome of 6173 bp comprising three major open reading frames. However, by detailed comparative genome and phylogenetic analysis, the virus was not clustered with the pre-existing genotypes, suggesting the emergence of a possible novel genotype of DHPV in cultured shrimps. This study is the first to report the complete genomic sequence of DHPV identified in P. vannamei.