Studies of adaptive evolution have experienced a recent revival in population genetics of natural populations and there is currently much focus on identifying genomic signatures of selection in space and time. Insights into local adaptation, adaptive response to global change and evolutionary consequences of selective harvesting can be generated through population genomics studies, allowing the separation of the effects invoked by neutral processes (drift-migration) from those due to selection. Such knowledge is important not only for improving our basic understanding of natural as well as human-induced evolutionary processes, but also for predicting future trajectories of biodiversity and for setting conservation priorities. Marine fishes possess a number of features rendering them well suited for providing general insights into adaptive genomic evolution in natural populations. These include well-described population structures, substantial and rapidly developing genomic resources and abundant archived samples enabling temporal studies. Furthermore, superior possibilities for conducting large-scale experiments under controlled conditions, due to the economic resources provided by the large and growing aquaculture industry, hold great promise for utilizing recent technological developments. Here, we review achievements in marine fish genomics to date and highlight potential avenues for future research, which will provide both general insights into evolution in high gene flow species, as well as specific knowledge which can lead to improved management of marine organisms.

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Although epidemiologic studies of tibial plateau fractures have been conducted, none have included geographically defined populations or a validated fracture classification based on computed tomography (CT). The goals of this study were to provide up-to-date information on the incidence and basic epidemiology of tibial plateau fractures in a large unselected patient population and to report the mechanisms of injury involved and the distribution of fractures according to a validated CT-based fracture classification. The authors conducted a population-based epidemiologic study of all patients treated for tibial plateau fracture over a 6-year period from 2005 to 2010. The study was based on an average background population of 576,364 citizens. A retrospective review of hospital records was performed. During this time, a total of 355 patients were treated for tibial plateau fracture. This group included 166 men and 189 women, and mean age was 52.6 years (SD, 18.3). The most common fracture type was AO type 41-B3, representing 35% of all tibial plateau fractures. The second most common fracture type was AO type 41-C3, representing 17% of all tibial plateau fractures. The incidence of tibial plateau fractures was 10.3 per 100,000 annually. Compared with women, men younger than 50 years had a higher incidence of fractures. The incidence of fractures increased markedly in women older than 50 years but decreased in men older than 50 years. In both sexes, the highest frequency was between the ages of 40 and 60 years.

Population structure was previously believed to be very limited or absent in classical marine fishes, but recently, evidence of weakly differentiated local populations has been accumulating using noncoding microsatellite markers. However, the evolutionary significance of such minute genetic differences remains unknown. Therefore, in order to elucidate the relationship between genetic markers and adaptive divergence among populations of marine fishes, we combined cDNA microarray and microsatellite analysis in European flounders (Platichthys flesus). We demonstrate that despite extremely low levels of neutral genetic divergence, a high number of genes were significantly differentially expressed between North Sea and Baltic Sea flounders maintained in a long-term reciprocal transplantation experiment mimicking natural salinities. Several of the differentially regulated genes could be directly linked to fitness traits. These findings demonstrate that flounders, despite little neutral genetic divergence between populations, are differently adapted to local environmental conditions and imply that adaptation in gene expression could be common in other marine organisms with similar low levels of population subdivision.

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Reduced representation genome sequencing such as RAD (Restriction-site Associated 2 DNA) sequencing is finding increased use to identify and genotype large numbers of 3 single nucleotide polymorphisms (SNPs) in model and non-model species. We 4 generated a unique resource of novel SNP markers for the European eel using the 5 RAD sequencing approach that were simultaneously identified and scored in a 6 genome-wide scan of 30 individuals. Whereas genomic resources are increasingly 7 becoming available for this species, including the recent release of a draft genome, no 8 genome-wide set of SNP markers was available until now. The generated SNPs were 9 widely distributed across the eel genome, aligning to 4,779 different contigs and 10 19,703 different scaffolds. Significant variation was identified, with an average 11 nucleotide diversity of 0.00529 across individuals. Results varied widely across the 12 genome, ranging from 0.00048 to 0.00737 per locus. Based on the average nucleotide 13 diversity across all loci, long-term effective population size was estimated to range 14 between 132,000 and 1,320,000, which is much higher than previous estimates based 15 on microsatellite loci. The generated SNP resource consisting of 82,425 loci and 16 376,918 associated SNPs provides a valuable tool for future population genetics and 17 genomics studies and allows for targeting specific genes and particularly interesting 18 regions of the eel genome.

The present study shows an incidence of 8.7/100,000/year of distal femur fractures. After the age of 60 years, a rapid increase in the incidence of distal femoral fractures was observed in both genders, with a considerable female predominance.

BackgroundOnce highly abundant, the European eel (Anguilla anguilla L.; Anguillidae; Teleostei) is considered to be critically endangered and on the verge of extinction, as the stock has declined by 90-99% since the 1980s. Yet, the species is poorly characterized at molecular level with little sequence information available in public databases.ResultsThe first European eel transcriptome was obtained by 454 FLX Titanium sequencing of a normalized cDNA library, produced from a pool of 18 glass eels (juveniles) from the French Atlantic coast and two sites in the Mediterranean coast. Over 310,000 reads were assembled in a total of 19,631 transcribed contigs, with an average length of 531 nucleotides. Overall 36% of the contigs were annotated to known protein/nucleotide sequences and 35 putative miRNA identified.ConclusionsThis study represents the first transcriptome analysis for a critically endangered species. EeelBase, a dedicated database of annotated transcriptome sequences of the European eel is freely available at http://compgen.bio.unipd.it/eeelbase. Considering the multiple factors potentially involved in the decline of the European eel, including anthropogenic factors such as pollution and human-introduced diseases, our results will provide a rich source of data to discover and identify new genes, characterize gene expression, as well as for identification of genetic markers scattered across the genome to be used in various applications.