title: Fine mapping QTL for resistance to VNN disease using a high-density linkage map in Asian seabass.
abstract: Asian seabass has suffered from viral nervous necrosis (VNN) disease. Our previous study has mapped quantitative trait loci (QTL) for resistance to VNN disease. To fine map these QTL and identify causative genes, we identified 6425 single nucleotide polymorphisms (SNPs) from 85 dead and 94 surviving individuals. Combined with 155 microsatellites, we constructed a genetic map consisting of 24 linkage groups (LGs) containing 3000 markers, with an average interval of 1.27 cM. We mapped one significant and three suggestive QTL with phenotypic variation explained (PVE) of 8.3 to 11.0%, two significant and two suggestive QTL with PVE of 7.8 to 10.9%, for resistance in three LGs and survival time in four LGs, respectively. Further analysis one QTL with the largest effect identified protocadherin alpha-C 2-like (Pcdhac2) as the possible candidate gene. Association study in 43 families with 1127 individuals revealed a 6 bp insertion-deletion was significantly associated with disease resistance. qRT-PCR showed the expression of Pcdhac2 was significantly induced in the brain, muscle and skin after nervous necrosis virus (NNV) infection. Our results could facilitate marker-assisted selection (MAS) for resistance to NNV in Asian seabass and set up the basis for functional analysis of the potential causative gene for resistance.
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive, Singapore 117543.|Temasek Life Sciences Laboratory, National University of Singapore, 1 Research Link, Singapore 117604.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.affiliation: Temasek Life Sciences Laboratory, National University of Singapore, 1 Research Link, Singapore 117604.
authors.forename: Le
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive, Singapore 117543.|Temasek Life Sciences Laboratory, National University of Singapore, 1 Research Link, Singapore 117604.|National University of Singapore Suzhou Research Institute, Suzhou, Jiangsu, China 215123.
authors.forename: Sek-Man
authors.initials: SM
authors.lastname: Wong
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive, Singapore 117543.|Temasek Life Sciences Laboratory, National University of Singapore, 1 Research Link, Singapore 117604.|School of Biological Sciences, Nanyang Technological University, 6 Nanyang Drive, Singapore 637551.
authors.forename: Gen Hua
authors.initials: GH
authors.lastname: Yue
mesh_terms: D000818:Animals; D015820:Cadherins / Q000235:genetics; D002874:Chromosome Mapping; D060467:Disease Resistance / Q000235:genetics*; D005393:Fish Diseases / Q000235:genetics* / Q000821:virology; D029941:Fish Proteins / Q000235:genetics; D005786:Gene Expression Regulation; D010473:Perciformes / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D012327:RNA Virus Infections / Q000662:veterinary / Q000821:virology
chemical_list: D015820:Cadherins; D029941:Fish Proteins