A new SNP-based vision of the genetics of sex determination in European sea bass (Dicentrarchus labrax)
|Author(s)||Palaiokostas Christos1, 2, Bekaert Michael1, Taggart John B.1, Gharbi Karim3, McAndrew Brendan J.1, Chatain Beatrice4, Penman David J.1, Vandeputte Marc4, 5|
|Affiliation(s)||1 : Univ Stirling, Sch Nat Sci, Inst Aquaculture, Stirling FK9 4LA, Scotland.
2 : Univ Edinburgh, Roslin Inst, Royal Dick Sch Vet Studies, Easter Bush EH25 9RG, Midlothian, Scotland.
3 : Univ Edinburgh, Edinburgh Genom, Ashworth Labs, Edinburgh EH9 3JT, Midlothian, Scotland.
4 : IFREMER, F-34250 Palavas Les Flots, France.
5 : INRA, Genet Anim & Biol Integrat UMR1313, F-78350 Jouy En Josas, France.
|Source||Genetics Selection Evolution (0999-193X) (Biomed Central Ltd), 2015-09 , Vol. 47 , N. 68 , P. 1-10|
|WOS© Times Cited||62|
|Abstract||Background: European sea bass (Dicentrarchus labrax) is one of the most important farmed species in Mediterranean aquaculture. The observed sexual growth and maturity dimorphism in favour of females adds value towards deciphering the sex determination system of this species. Current knowledge indicates the existence of a polygenic sex determining determination system that interacts with temperature. This was explored by restriction-site associated DNA (RAD) marker analysis in a test panel of 175 offspring that originated from a factorial cross between two dams and four sires from a single full-sib family.
Results: The first high-density single nucleotide polymorphism (SNP) based linkage map for sea bass was constructed, consisting of 6706 SNPs on 24 linkage groups. Indications for putative sex-determining QTL (quantitative trait loci) that were significant at the genome-wide threshold were detected on linkage groups 6, 11 and 18 to 21, although a genome-wide association study (GWAS) did not identify individual significant SNPs at a genome-wide threshold. A preliminary genomic prediction approach that tested the efficiency of SNP-based selection for female sea bass showed a slight advantage compared to traditional pedigree-based selection. However, when the same models were tested on the same animals for selection for greater length, a clear advantage of the SNP-based selection was observed.
Conclusions: Overall, the results of this study provide additional support to the polygenic sex determination hypothesis in sea bass. In addition, identification of sex-ratio QTL may provide new opportunities for sex-ratio control in sea bass.