African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12291

Full Length Research Paper

Genetic variation and population structure of willowy flounder Tanakius kitaharai collected from Aomori, Ibaraki and Niigata in Northern Japan

Yongshuang Xiao1, Masakazu Takahashi4, Takashi Yanagimoto2, Yan Zhang3,Tianxiang Gao1*, Mamoru Yabe4 and Yasunori Sakurai4
  1Key Laboratory of Mariculture, Ministry of Education of China, Ocean University of China, Qingdao, 266003, China. 2National Research Institute of Far Seas Fisheries, Fukuura, Kanazawa-ku, Yokohama, 236-8648, Japan. 3Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China. 4Graduate School of Fisheries Sciences, Hokkaido University, Minato-cho, Hakodate, Hokkaido, 041-8611, Japan.
Email: [email protected]

  •  Accepted: 03 July 2008
  •  Published: 05 November 2008



The first hypervariable region (HVR-1) of the mitochondrial DNA control region was utilized for determination of genetic variation and population structure in willowy flounder (Tanakius kitaharai) collected from Aomori, Ibaraki and Niigata. A total of 35 haplotypes were detected among 66 individuals with a total of 30 variable sites out of 387 bp sequenced. Average sequence differences between populations (1.0 - 1.1%) were comparable to those within populations (0.9 - 1.2%), suggesting no genetic heterogeneity among samples. The pattern of distribution of genetic variability with high level of haplotype diversity (= 0.94) and moderate nucleotide diversity (л = 1.0%) was also detected in the HVR-1 region of the mitochondrial DNA control region. AMOVA tests and the conventional population Φst comparisons revealed no significant genetic structure among the populations. Partitioning populations into coherent geographic groups divided willowy flounder samples (Φct= -0.007, P > 0.05) into two major groups: a Sea of Japan group composed of Aomori and Niigata populations; a Pacific Ocean group composed of Ibaraki populations. The minimum spanning tree constructed with 35 haplotypes showed four low-divergent clades, corresponding to those defined in the NJ tree. However, these clades did not appear to have geographic structure. Altogether, the results indicate that willowy flounder is panmictic throughout the examined range in Aomori, Ibaraki and Niigata.


Key words: Tanakius kitaharai, mitochondrial DNA control region, genetic variability, genetic structure.


HVR-1, The first hypervariable region; AMOVA, Analysis of molecular variance.