title: Correlation between grass carp (Ctenopharyngodon idella) resistance to grass carp reovirus and the genetic insert-deletion polymorphisms in promoter and intron of RIG-I gene.
abstract: RIG-I (retinoic acid-inducible gene I) is an essential cytosolic pathogen recognition receptor that binds to a variety of viral RNA or DNA to induce type I interferons. In the present study, insert-deletion polymorphisms in promoter and introns of CiRIG-I (Ctenopharyngodon idella RIG-I) were explored, their associations with resistance/susceptibility to grass carp reovirus (GCRV) were analyzed. To this end, genomic sequence of CiRIG-I gene was obtained, and twenty pairs of primers were prepared for the detection of insert-deletion polymorphisms. Five insert-deletion mutations were found, a 2-bp mutation and an 8-bp mutation existed in the promoter and other three sizes in 74 bp, 146 bp and 53 bp were sited in the intron 8. After a challenge experiment, only the genotype and allele of -740 insert-deletion mutation in the promoter and allele of 6804 insert-deletion mutation were significantly associated with resistance/susceptibility to GCRV among the five mutations (P<0.05). To further identify this correlation, another independent challenge test was carried out. The result revealed that the cumulative mortality in ins/ins genotype individuals (43.75%) at -740 insert-deletion mutation was significantly lower than that in ins/del (72.09%) and del/del (74.19%) genotypes (P<0.05). Linkage disequilibrium and haplotype analysis showed 6610 insert-deletion mutation and 6804 insert-deletion mutation were linkage disequilibrium. The haplotype ins-ins (6610ins-6804ins) was significantly susceptible to GCRV, and ins-del (6610ins-6804del) was significantly resistant to GCRV (P<0.05). Those could be potential gene markers for the future molecular selection of strains that are resistant to GCRV.
authors.affiliation: College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China.
authors.forename: Quanyuan
authors.initials: Q
authors.lastname: Wan
authors.forename: Jianguo
authors.initials: J
authors.lastname: Su
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
authors.forename: Limin
authors.initials: L
authors.lastname: Peng
authors.forename: Lijun
authors.initials: L
authors.lastname: Chen
mesh_terms: D000818:Animals; D001483:Base Sequence; D002347:Carps / Q000235:genetics / Q000276:immunology; D060467:Disease Resistance / Q000235:genetics*; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology; D020022:Genetic Predisposition to Disease; D054643:INDEL Mutation / Q000502:physiology; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic / Q000502:physiology; D011401:Promoter Regions, Genetic / Q000235:genetics; D020365:RNA Helicases / Q000235:genetics*; D012087:Reoviridae / Q000276:immunology*; D012088:Reoviridae Infections / Q000235:genetics* / Q000276:immunology
chemical_list: D020365:RNA Helicases