Genome-wide association study reveals multiple novel SNPs and putative candidate genes associated with low oxygen tolerance in golden pompano Trachinotus ovatus (Linnaeus 1758)

Golden pompano (Trachinotus ovatus) is one of the most economically critical marine fishes in South China. Low oxygen stress, which is caused by a variety of factors, has resulted in substantial economic losses to the aquaculture of golden pompano. Genome-wide association study (GWAS) has been widely used to study the genetic basis of important economic traits in aquatic animals. In the present study, 100 individuals were used for genome-wide association study of hypoxia tolerance trait based on genome-wide resequencing technology to explore the SNPs and related candidate genes affecting hypoxia tolerance trait in golden pompano. Four significant SNPs were identified to be suggestively significantly associated with the hypoxia tolerance trait. In the 50 kb window surrounding the suggestive SNPs, 16 potential candidate genes affecting hypoxia tolerance trait were detected. Moreover, validation results of the screened significant loci in the large population were consistent with the results of the GWAS. Among these results, the survival times of individuals with different genotypes at SNP24101852 and SNP24194184 were significantly different (p < 0.01). These results have specific guiding significance for the genetic improvement and determining the molecular mechanism of hypoxia tolerance. These SNPs could be used as molecular markers to screen for hypoxia tolerance be used for further applications in the heritage breeding of golden pompano.