Genetic structure, polymorphism identification of LGP2 gene and their relationship with the resistance/susceptibility to GCRV in grass carp, Ctenopharyngodon idella.

Abstract Laboratory of genetics and physiology 2 (LGP2) is an actual detector and regulator during RNA viral infection in innate immunity. In this study, 5′-flanking region and all introns of LGP2 in grass carp ( Ctenopharyngodon idella ) were excavated. The genomic CiLGP2 ( C. idella LGP2 ) was 8062 bp in length, with a 364 bp 5′-flanking region, twelve exons and eleven introns. Besides, the promoter activity of the upstream region before initiator codon was identified. By sequencing, six single nucleotide polymorphisms (SNPs) and one 20-bp insertion/deletion polymorphism were detected in CiLGP2 . With a challenge experiment, the genotype and allele distributions of these seven polymorphisms were examined. Analytic result revealed only the − 1392 C/G, 494 A/T and 4403 C/T loci were significantly associated with the resistance/susceptibility to grass carp reovirus (GCRV) (P  C. idella strains that are resistant to GCRV.