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Bigeye tuna Thunnus obesus is considered an important fishery species around the world. There is no adequate genetic data available for the T. obesus population. Polymorphism of sequence variations in mitochondrial Cyt b genes were assessed to explore the level of genetic variability and differentiation among eight populations of T. obesus sampled from the central Pacific Ocean. Overall, a total of 44 mtDNA haplotypes and 26 variable sites were detected in the 686 bp segment of mtDNA Cyt b gene. Nucleotide diversity ranged from 0.17 to 0.27 % and the haplotype diversity ranged from 0.604 to 0.793. An analysis of molecular variance (AMOVA) test of bigeye tuna revealed that 99.38 % of the genetic variation occurred within populations. Both the maximum likelihood tree and the haplotype network indicated that two lineages of bigeye tuna coexisted in the central Pacific Ocean. Hierarchical AMOVA tests and pairwise analysis revealed no geographical isolation among haplotypes within the two lineages. High Nm values from this investigation indicated high rates of gene flow between the two sampling regions. Furthermore, tests of neutrality and mismatch distribution suggested that T. obesus might have experienced a population expansion, one that possibly occurred 110,000 years ago. Our study firstly unraveled the population genetic structure of the T. obesus in the central Pacific Ocean, and addressed the related fishery management issues including fishery stock identification, management, and conservation. [ABSTRACT FROM AUTHOR]

In this study, we determined the complete mitogenome sequence ofPseudocarcharias kamoharai. The complete mitogenome ofP. kamoharaiis 16,694 bp in length, which contains 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs and 2 non-coding regions: control region (D-loop) and origin of light-strand replication (OL). Overall, base composition of mitogenome is estimated to be 32.06% for A, 23.63% for C, 13.21% for G and 31.10% for T. The complete mtDNA sequence ofP. kamoharaiprovides a useful data for the studies on the molecular systematic phylogeography and population genetics. [ABSTRACT FROM PUBLISHER]

Abstract: Portunus trituberculatus is a commercially important fishery species. In this study, intraspecific variation was examined by using mitochondrial DNA 16S rRNA gene in 213 individual crabs sampled from six localities along the coast of the East China Sea. Twenty-two polymorphic sites defined 25 distinct haplotypes, revealing a moderately high haplotype diversity and relatively low sequence divergence among the six localities. An excess of within population unique haplotypes at most sample locations were detected, which might influence genetic structure of the swimming crab populations. Neither neighbor-joining tree nor minimum spanning network (MSN) based on the haplotype data indicated distinct patterns of phylogeographic structure among the 25 haplotypes. Analyses of molecular variance (AMOVA) and F ST statistics supported the hypothesis that population samples from the East China Sea were genetically nonhomogenous, indicating that gene flow might be restricted across those regions, despite the high potential of dispersal. In addition, tests of neutral evolution and analysis of mismatch distribution suggested that P. trituberculatus might have undergone a population expansion, possibly within the last 127,000 and 429,000 years. Our study unraveled the extant population genetic structure of the P. trituberculatus, and addressed the related fishery management issues including artificial breeding, fishery stock identification and conservation. [Copyright &y& Elsevier]

Portunus trituberculatus is a commercially important species widely spread in the East China Sea. Intraspecific variation of the mitochondrial DNA cytochrome oxidase subunit I (mtDNA COI) gene was investigated in 213 individuals from six localities (Changjiang Estuary, Shengsi Islands, Zhoushan Islands, Dongtou Islands, Dinghai Bay, and Quanzhou Bay) ranging from north (31°21′N) to south (24°55′N) coastal waters of the East China Sea. Overall, a total of 27 mtDNA haplotypes and 21 variable sites were detected in the 787 bp segment of COI gene. Analysis of mtDNA COI sequence data revealed that crabs from the six localities were characterized by moderately high haplotypic diversity ( h = 0.787 ± 0.026), while sequence divergence values between haplotypes were relatively low (π = 0.00241 ± 0.00098). Each population was characterized by a single most frequent haplotype, shared among all six localities, and a small number of rare ones, typically present in only one or two individuals and representative of a specific population. However, neither the neighbor-joining tree nor the minimum spanning network (MSN) based on the haplotype data exhibited geographical patterns of the six populations. Mismatch distribution analysis of P. trituberculatus individuals sampled from the six localities suggested that sudden population expansion might have occurred in CJ and SS population that might be consistent with over-exploitation of the swimming crab. Analysis of molecular variance (AMOVA) and F ST statistics showed that significant genetic differentiation existed among the SS, ZS, DT, DH, and QZ populations, suggesting that gene flow might be reduced, even between the geographically close sites, despite the high potential of dispersal. The possible causes of the observed genetic heterogeneity among the P. trituberculatus populations and the potential applications of the mtDNA COI marker in the artificial breeding and fisheries... [ABSTRACT FROM AUTHOR]

In this study, the complete mitochondrial DNA ofSchizothorax gongshanensiswas determined. The complete genome is 16,591 bp in length which contains 13 protein-coding genes, 22 transfer RNA genes, 2 rRNA genes, an origin of light-strand replication (OL) and a control region (D-Loop). The complete mtDNA sequence ofS. gongshanensisprovides a useful genetic marker for the studies on molecular systematics, population genetics and stock assessment. [ABSTRACT FROM PUBLISHER]

In this study, the complete mitochondrial DNA (mtDNA) sequence ofSchizothorax yunnanensis paoshanensisis determined for the first time. The complete mtDNA genome sequence ofS. yunnanensis paoshanensisis 16,585 bp in length. It consists of 13 protein-coding genes, 22 transfer RNA genes, 2 rRNA genes and a putative control region (D-loop region). The gene order ofS. yunnanensis paoshanensismtDNA is identical to most of the vertebrate mtDNAs. The complete mitogenome sequence information ofS. yunnanensis paoshanensiscan provide useful data for further studies on molecular systematics, taxonomic status and conservation genetics. [ABSTRACT FROM AUTHOR]

The complete mitochondrial DNA sequence ofCarcharhinus longimanuswas determined and analyzed. The complete mtDNA genome sequence ofC. longimanuswas 16,706 bp in length. It contained 22 tRNA genes, 2 rRNA genes, 13 protein-coding genes and 2 non-conding regions: control region (D-loop) and origin of light-strand replication (OL). The complete mitogenome sequence information ofC. longimanuscan provide a useful data for further studies on molecular systematics, stock evaluation, taxonomic status and conservation genetics. [ABSTRACT FROM PUBLISHER]

A correction to the article "Genetic Population Structure of Thunnus albacares in the Central Pacific Ocean Based on mtDNA COI Gene Sequences" that was published in the 2015 issue is presented.

Gymnocypris dobula is a commercially important fishery species and mostly distributed in the freshwater of Tibetan plateau. In this study, genetic diversity and intraspecific population differentiation were examined by using mitochondrial DNA D-loop sequences in 97 individuals sampled from three localities (Pali, Lasa and Yanghu) in the Tibetan plateau. Two hundred and fourteen polymorphic sites and 50 haplotypes were defined among the three localities. Genetic diversity analysis showed that the highest genetic diversity level was found in Pali population. Phylogenetic relationships analysis results indicated that closer phylogenetic relationships were found between the Yanghu and Lasa populations. Genetic population differentiation analysis indicated that the majority of variation (84.91%) was attributed to variations among populations and the largest differentiation was found between Pali and Lasa localities ( F st = 0.874, Nm = 0.036). Moreover, the historical demographic events were assessed by implementing the mismatch distribution analysis, Fajima's D test and Fu's Fs test. The results indicated that the Pali population had undergone a demographic expansion, possibly within the last 0.163 MYA (Million Years Ago). Our study firstly identified the population genetic structure of the G. dobula , which could be helpful for artificial breeding, fishery stock identification and resource conservation for this species. [ABSTRACT FROM AUTHOR]