Genetic population evaluation of two closely related flatfish species, the rare barfin flounder and spotted halibut, along the Japanese coast

Abstract

Barfin flounder and spotted halibut have been selected as target species for stock enhancement in Japan. Understanding the genetic condition of the wild stock is a principal requirement in any stock enhancement program. The genetic variability of barfin flounder and spotted halibut, and the population structure of spotted halibut were evaluated using microsatellite DNA markers (msDNA) and the control region of the mitocondrial DNA (mtDNA). Barfin flounder and spotted halibut showed high genetic variability at the msDNA level. Barfin flounder A was 16.7 and H e was 0.860; spotted halibut A n ranged from 7.7 to 10.2 and H e ranged from 0.710 to 0.774. At the mtDNA level, high haplotype (h = 0.922) and low nucleotide (π = 0.002) diversities were observed for barfin flounder; however, low haplotype and nucleotide diversities (h = 0.603-0.620 and π = 0.001-0.002), and very low haplotype and nucleotide diversities (h = 0.193 and π = 0.0003) were observed for spotted halibut in the north and south locations, respectively. Slight genetic differentiation among spotted halibut sampling locations was observed from the msDNA. MtDNA analyses showed genetic differentiation between north and south locations, but not within them. The designation of north-specific and south-specific management units in the future stock enhancement activities of spotted halibut is recommended.

Fine-scale population genetic structure in Alaskan Pacific halibut (Hippoglossus stenolepis)

“…The H. stenolepis mtDNA sequence was confirmed by alignment with the published sequence for the mtDNA control region of the Japanese barfin flounder (Verasper moseri) also in the Family Pleuronectidae (GENBANK Accession #AB207249; Ortega-Villaizán Romo et al 2006). Standard diversity indices (number of haplotypes, haplotype diversity and nucleotide diversity) were assessed by region and regional mtDNA haplotype frequencies were analyzed using ARLEQUIN v3.01.…”

Isolation of sex-specific AFLP markers in Spotted Halibut (Verasper variegatus)

“…Previous studies about Spotted Halibut have mainly focused on growth and development (Koya et al 2003;Wada et al 2006), genetic population structure (Ortega-Villaizan et al 2006;Ma et al 2009b) and chromosome karyotype (Sha et al 2007). However, the inability to rapidly identify the genetic sex of Spotted Halibut has hampered seriously the development of sex control research.…”

Genetic structure of wild brown sole inferred from mitochondrial DNA analysis

“…The frequency of variable sites, which is often used in estimates of nucleotide and haplotypic diversities, in the mtDNA control region in brown sole (about 24%) was lower than that of olive flounder (36%) reported by Fujii and Nishida (1997), and that of summer flounder (34%) reported by Jones and Quattro (1999), but greater than that of barfin flounder (1.3%) reported by Ortega-Villaizan Romo et al (2006). Although the result by Ortega-Villaizan Romo et al (2006) was obtained from a small sample size (n 022), the level of variation at 10 sites out of 765 bp of the mtDNA control region was extremely low.…”

“…The primer sets were designed for an approximately 484 bp portion from the 5? end according to the control region sequence excluding tandem repeats of barfin flounder deposited in the NCBI Genbank (accession number AB207249; OrtegaVillaizan Romo et al 2006). PCR was performed in a 15 ml reaction mixture containing a 50Á100 ng DNA template.…”