Development and use of microsatellite markers in sea bass, Dicentrarchus labrax (Linnaeus, 1758) (Perciformes: Serrandidae).

The first microsatellite markers in sea bass, Dicentrarchus labrax, are described. Microsatellite-containing clones were isolated from a genomic library, their DNA sequences determined, and polymerase chain reaction primers designed for seven dinucleotide microsatellite loci. All microsatellites were shown to be highly polymorphic: six unrelated individuals displayed 86% observed heterozygosity and an average of 7.6 alleles per locus. Inheritance was shown to be Mendelian by analysis of genotypic ratios in F1 offspring. An analysis of 97 mass-reared offspring of a complete diallel cross between three males and three females showed that the parentage of all individuals could be determined unambiguously after scoring one locus in all individuals, followed by scoring a second locus in 24 individuals. The results suggest that microsatellites will be valuable tools in studies of sea bass for genetic tagging, marker-assisted selection programs, and identification of natural stocks.