Identification of Growth Hormone (GH) Gene Polymorphisms and Their Association with Growth Traits in European Sea Bass (Dicentrarchus labrax)

Abstract The growth hormone (GH) gene has an important regulatory roles in postnatal somatic growth, metabolism and development of vertebrates and fish. The aim of this study was to identify the genetic variation of the GH gene and its associations with growth traits by DNA sequencing in 200 European sea bass (Dicentrarchus labrax) individuals. Ten novel SNPs were identified as g.1557 A > T, g.1611 T > C, g.1663 C > G, g.1799 T > C, g.1824 T > C, g.1912 T > A, g.2052 G > C in the 1st partial intron, 2nd exon, 2nd intron and 3rd partial exon of GH gene in European sea bass. The genotypes of GH g.1611 T > C locus were found associated with total weight, fillet weight and head length (p < 0.05). Association between the genotypes of GH g.1557A > T and pre-anal length, abdominal length were found statistically significant (p < 0.05). Similarly, the genotypes of GH g.1799 T > C locus which caused the amino acid change from Leucine to Serine (L8S) were found related to body length and abdominal length (p < 0.05). This amino acid change also caused the 3D tertiary structure of the GH peptide. Thus, these SNPs have an effect on the growth traits of European sea bass and could be used for genomic selection in European sea bass breeding.