Construction of high-density genetic linkage map and QTL mapping for growth performance in black carp (Mylopharyngodon piceus)

Abstract

Growth related traits controlled by quantitative trait loci (QTL) are important economic traits in aquaculture fish species. In order to dissect these QTL, a high-density genetic linkage map is particularly important. In this study, the first high-density genetic linkage map of black carp ( Mylopharyngodon piceus ) was constructed using one F 1 family comprising of 128 progenies, based on genotyping-by-sequencing (GBS). A total of 10,390 single nucleotide polymorphisms (SNPs) were discovered and genotyped. A number of 4108 high-quality SNPs were assigned to 24 linkage groups (LGs) and the total length of the map was 1708.53 cM with a resolution of 0.51 cM. Conserved syntenic relationship between the high-density linkage map and the zebrafish chromosomes was detected. Relying on this high-density linkage map, 17 suggestive QTL: one for body weight, four for body length, six for body height, and six for body wide, were identified on three linkage groups (LG10, LG17, LG20). The phenotypic variance explained (PVE) by these QTL ranged from 10.9 to 15.5%. The high-density genetic linkage map serves as valuable genomic resources not only for understanding the genomic basis of economically important traits in this fish species, but also for comparative genomics and evolutionary studies of black carp. The identified QTL provide important value for ongoing marker assisted selection (MAS) in this fish. • The first genetic linkage map for black carp with an average resolution of 0.51 cM per locus was constructed using 4197 SNPs • 17 QTL related to body weight, body length, body width and body height were identified on three linkage groups • The LG1 in black carp corresponding to Chr10 and Chr22 in zebrafish genome.