A molecular insight into the resistance of yellow drum to Vibrio harveyi by genome-wide association analysis

Abstract

Yellow drum (Nibea albiflora), a commercially important fish species in the coastal regions of southeast China, suffers greatly from attacks from bacteria, viruses, and parasites. To uncover their immune responses, the yellow drums were artificially challenged with the pathogenic Vibrio harveyi, and genome-wide association study (GWAS) was performed to identify the associated SNPs and genetic loci for disease resistance trait. Sequence analysis in 197 susceptible and 148 resistant fish identified 23 significantly associated SNPs and 8 candidate genes distributed in chromosome 14. The estimated proportion of phenotypic variance explained (PVE) by SNPs ranged from 10.64% to 13.68%. The discovery of sphingosine kinase (SPHK), CACNA1H, and MGAT5B harboring or within the flanking region of trait-associated SNPs may account for the underlying antibacterial mechanism in yellow drum. These results provide molecular basis for prevention of disease spread and a reference for genetic breeding in fish aquaculture.