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1.
Evol Appl ; 17(4): e13688, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38633132

RESUMO

Elucidating the effects of domesticated organisms escaping into the natural environment represents a topic of importance in both evolutionary and conservation biology. However, when excluding the abundant data on salmonids, there is a lack of knowledge on this topic for marine fish aquaculture, which continues to expand globally. In order to bridge this empirical gap, we investigated a suspected escape of sexually mature domesticated Atlantic cod from a commercial marine fish farm in northern Norway. This involved genotyping samples of fish from cages on the farm, putatively identified escapees and wild cod captured in the region and samples of recently spawned eggs collected in the sea. Genetic analyses confirmed a farmed ancestry of the suspected escapees, and significantly, 27% of the sampled cod eggs. Furthermore, statistical analyses revealed a strong reduction in genetic variation in all samples of the farmed cod, including low effective population size and high degree of siblingship. These results thus document the escape of sexually mature adult cod and the release of fertilized domesticated cod eggs into the natural environment. Although it is possible that some of the mature escapees spawned post-escape, the fact that only a single egg of potential hybrid farmed × wild origin was identified, together with the high number of mature cod in the farm, points to within cage spawning as the primary source of these eggs. This suggestion is supported by oceanic particle-drift modelling, verifying that transport of eggs between the farm and the egg sampling locations was plausible. This study represents a rare documentation of interaction between domesticated and wild populations for a marine fish, pointing towards potential impacts on the local wild population.

2.
Mol Ecol Resour ; 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37681405

RESUMO

The Harbour porpoise (Phocoena phocoena) is a highly mobile cetacean species primarily occurring in coastal and shelf waters across the Northern hemisphere. It inhabits heterogeneous seascapes broadly varying in salinity and temperature. Here, we produced 74 whole genomes at intermediate coverage to study Harbour porpoise's evolutionary history and investigate the role of local adaptation in the diversification into subspecies and populations. We identified ~6 million high quality SNPs sampled at eight localities across the North Atlantic and adjacent waters, which we used for population structure, demographic and genotype-environment association analyses. Our results suggest a genetic differentiation between three subspecies (P.p. relicta, P.p. phocoena and P.p. meridionalis), and three distinct populations within P.p. phocoena: Atlantic, Belt Sea and Proper Baltic Sea. Effective population size and Tajima's D suggest population contraction in Black Sea and Iberian porpoises, but expansion in the P.p. phocoena populations. Phylogenetic trees indicate post-glacial colonization from a southern refugium. Genotype-environment association analysis identified salinity as major driver in genomic variation and we identified candidate genes putatively underlying adaptation to different salinity. Our study highlights the value of whole genome resequencing to unravel subtle population structure in highly mobile species, shows how strong environmental gradients and local adaptation may lead to population differentiation, and how neutral and adaptive markers can give different perspectives on population subdivision. The results have great conservation implications as we found inbreeding and low genetic diversity in the endangered Black Sea subspecies and identified the critically endangered Proper Baltic Sea porpoises as a separate population.

3.
Evol Appl ; 16(7): 1328-1344, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37492153

RESUMO

Resistance toward the antiparasitic pyrethroid, deltamethrin, is reported in the Atlantic salmon louse (Lepeophtheirus salmonis salmonis), a persistent ectoparasite of farmed and wild salmonids. The resistance mechanism is linked to mitochondrial DNA (mtDNA), where genetic markers for resistance have been identified. Here, we investigated how widespread pyrethroid use in aquaculture may have influenced mtDNA variation in lice, and the dispersion of resistant haplotypes across the North Atlantic, using historical (2000-2002 "pre-resistance") and contemporary (2014-2017 "post-resistance") samples. To study this, we sequenced ATPase 6 and cytochrome b, genotyped two genetic markers for deltamethrin resistance, and genotyped microsatellites as "neutral" controls of potential population bottlenecks. Overall, we observed a modest reduction in mtDNA diversity in the period 2000-2017, but no reduction in microsatellite variation was observed. The reduction in mtDNA variation was especially distinct in two of the contemporary samples, fixed for one and two haplotypes, respectively. By contrast, all historical samples consisted of close to one mtDNA haplotype per individual. No population genetic structure was detected among the historical samples for mtDNA nor microsatellites. By contrast, significant population genetic differentiation was observed for mtDNA among some of the contemporary samples. However, the observed population genetic structure was tightly linked with the pattern of deltamethrin resistance, and we therefore conclude that it primarily reflects the transient mosaic of pyrethroid usage in time and space. Two historically undetected mtDNA haplotypes dominated in the contemporary samples, both of which were linked to deltamethrin resistance, demonstrating primarily two origins of deltamethrin resistance in the North Atlantic. Collectively, these data demonstrate that the widespread use of pyrethroids in commercial aquaculture has substantially altered the patterns of mtDNA diversity in lice across the North Atlantic, and that long-distance dispersion of resistance is rapid due to high level of genetic connectivity that is observed in this species.

4.
PLoS One ; 18(3): e0283351, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36940210

RESUMO

Lumpfish (Cyclopterus lumpus) is a transatlantic marine fish displaying large population sizes and a high potential for dispersal and gene-flow. These features are expected to result in weak population structure. Here, we investigated population genetic structure of lumpfish throughout its natural distribution in the North Atlantic using two approaches: I) 4,393 genome wide SNPs and 95 individuals from 10 locations, and II) 139 discriminatory SNPs and 1,669 individuals from 40 locations. Both approaches identified extensive population genetic structuring with a major split between the East and West Atlantic and a distinct Baltic Sea population, as well as further differentiation of lumpfish from the English Channel, Iceland, and Greenland. The discriminatory loci displayed ~2-5 times higher divergence than the genome wide approach, revealing further evidence of local population substructures. Lumpfish from Isfjorden in Svalbard were highly distinct but resembled most fish from Greenland. The Kattegat area in the Baltic transition zone, formed a previously undescribed distinct genetic group. Also, further subdivision was detected within North America, Iceland, West Greenland, Barents Sea, and Norway. Although lumpfish have considerable potential for dispersal and gene-flow, the observed high levels of population structuring throughout the Atlantic suggests that this species may have a natal homing behavior and local populations with adaptive differences. This fine-scale population structure calls for consideration when defining management units for exploitation of lumpfish stocks and in decisions related to sourcing and moving lumpfish for cleaner fish use in salmonid aquaculture.


Assuntos
Doenças dos Peixes , Perciformes , Animais , Peixes/genética , Islândia , Aquicultura , Groenlândia
5.
Evol Appl ; 15(7): 1162-1176, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35899259

RESUMO

Identifying how physical and biotic factors shape genetic connectivity among populations in time and space is essential to our understanding of the evolutionary trajectory as well as the management of marine species. Atlantic cod is a widespread and commercially important marine species displaying several ecotypes with different life history strategies. Using three sets of SNPs: neutral, informative, and genome-inversion linked, we studied population genetic structure of ~2500 coastal Atlantic cod (CC) from 40 locations along Norway's 2500 km coastline, including nine fjords. We observed: (1) a genetic cline, suggesting a mechanism of isolation by distance, characterized by a declining F ST between CC and North East Arctic Cod (NEAC-genetically distinct migratory ecotype) with increasing latitude, (2) that in the north, samples of CC from outer-fjord areas were genetically more similar to NEAC than were samples of CC from their corresponding inner-fjord areas, (3) greater population genetic differentiation among CC sampled from outer-fjord areas along the coast, than among CC sampled from their corresponding inner-fjord areas, (4) genetic differentiation among samples of CC from both within and among fjords. Collectively, these results permit us to draw two main conclusions. First, that differences in the relative presence of the genetically highly distinct, migratory ecotype NEAC, declining from north to south and from outer to inner fjord, plays the major role in driving population genetic structure of the Norwegian CC. Second, that there is limited connectivity between CC from different fjords. These results suggest that the current management units implemented for this species in Norway should be divided into smaller entities. Furthermore, the situation where introgression from one ecotype drives population genetic structure of another, as is the case here, may exist in other species and geographical regions, thus creating additional challenges for sustainable fisheries management.

6.
BMC Ecol Evol ; 21(1): 143, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256705

RESUMO

BACKGROUND: In species showing partial migration, as is the case for many salmonid fishes, it is important to assess how anthropogenic pressure experienced by migrating individuals affects the total population. We focused on brown trout (Salmo trutta) from the Guddal River in the Norwegian Hardanger Fjord system, which encompasses both resident and anadromous individuals. Aquaculture has led to increased anthropogenic pressure on brown trout during the marine phase in this region. Fish traps in the Guddal River allow for sampling all ascending anadromous spawners and descending smolts. We analyzed microsatellite DNA markers from all individuals ascending in 2006-2016, along with all emigrating smolts in 2017. We investigated (1) if there was evidence for declines in census numbers and effective population size during that period, (2) if there was association between kinship and migration timing in smolts and anadromous adults, and (3) to what extent resident trout were parents of outmigrating smolts. RESULTS: Census counts of anadromous spawners showed no evidence for a decline from 2006 to 2016, but were lower than in 2000-2005. Estimates of effective population size also showed no trends of declines during the study period. Sibship reconstruction of the 2017 smolt run showed significant association between kinship and migration timing, and a similar association was indicated in anadromous spawners. Parentage assignment of 2017 smolts with ascending anadromous trout as candidate parents, and assuming that unknown parents represented resident trout, showed that 70% of smolts had at least one resident parent and 24% had two resident parents. CONCLUSIONS: The results bear evidence of a population that after an initial decline has stabilized at a lower number of anadromous spawners. The significant association between kinship and migration timing in smolts suggests that specific episodes of elevated mortality in the sea could disproportionally affect some families and reduce overall effective population size. Finally, the results based on parentage assignment demonstrate a strong buffering effect of resident trout in case of elevated marine mortality affecting anadromous trout, but also highlight that increased mortality of anadromous trout, most of which are females, may lower overall production in the system.


Assuntos
Migração Animal , Truta , Animais , Aquicultura , Estuários , Feminino , Humanos , Rios
7.
Evol Appl ; 14(6): 1572-1587, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34178105

RESUMO

Translocation and introduction of non-native organisms can have major impacts on local populations and ecosystems. Nevertheless, translocations are common practices in agri- and aquaculture. Each year, millions of wild-caught wrasses are transported large distances to be used as cleaner fish for parasite control in marine salmon farms. Recently, it was documented that translocated cleaner fish are able to escape and reproduce with local wild populations. This is especially a challenge in Norway, which is the world's largest salmon producer. Here, a panel of 84 informative SNPs was developed to identify the presence of nonlocal corkwing wrasse (Symphodus melops) escapees and admixed individuals in wild populations in western Norway. Applying this panel to ~2000 individuals, escapees and hybrids were found to constitute up to 20% of the local population at the northern edge of the species' distribution. The introduction of southern genetic material at the northern edge of the species distribution range has altered the local genetic composition and could obstruct local adaptation and further range expansion. Surprisingly, in other parts of the species distribution where salmon farming is also common, few escapees and hybrids were found. Why hybridization seems to be common only in the far north is discussed in the context of demographic and transport history. However, the current lack of reporting of escapes makes it difficult to evaluate possible causes for why some aquaculture-dense areas have more escapees and hybrids than others. The results obtained in this study, and the observed high genomic divergence between the main export and import regions, puts the sustainability of mass translocation of nonlocal wild wrasse into question and suggests that the current management regime needs re-evaluation.

8.
Ecol Evol ; 11(4): 1691-1718, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33613998

RESUMO

Habitat changes represent one of the five most pervasive threats to biodiversity. However, anthropogenic activities also have the capacity to create novel niche spaces to which species respond differently. In 1880, one such habitat alterations occurred in Landvikvannet, a freshwater lake on the Norwegian coast of Skagerrak, which became brackish after being artificially connected to the sea. This lake is now home to the European sprat, a pelagic marine fish that managed to develop a self-recruiting population in barely few decades. Landvikvannet sprat proved to be genetically isolated from the three main populations described for this species; that is, Norwegian fjords, Baltic Sea, and the combination of North Sea, Kattegat, and Skagerrak. This distinctness was depicted by an accuracy self-assignment of 89% and a highly significant F ST between the lake sprat and each of the remaining samples (average of ≈0.105). The correlation between genetic and environmental variation indicated that salinity could be an important environmental driver of selection (3.3% of the 91 SNPs showed strong associations). Likewise, Isolation by Environment was detected for salinity, although not for temperature, in samples not adhering to an Isolation by Distance pattern. Neighbor-joining tree analysis suggested that the source of the lake sprat is in the Norwegian fjords, rather than in the Baltic Sea despite a similar salinity profile. Strongly drifted allele frequencies and lower genetic diversity in Landvikvannet compared with the Norwegian fjords concur with a founder effect potentially associated with local adaptation to low salinity. Genetic differentiation (F ST) between marine and brackish sprat is larger in the comparison Norway-Landvikvannet than in Norway-Baltic, which suggests that the observed divergence was achieved in Landvikvannet in some 65 generations, that is, 132 years, rather than gradually over thousands of years (the age of the Baltic Sea), thus highlighting the pace at which human-driven evolution can happen.

9.
Evol Appl ; 13(10): 2673-2688, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33294016

RESUMO

Challenging long-held perceptions of fish management units can help to protect vulnerable stocks. When a fishery consisting of multiple genetic stocks is managed as a single unit, overexploitation and depletion of minor genetic units can occur. Atlantic cod (Gadus morhua) is an economically and ecologically important marine species across the North Atlantic. The application of new genomic resources, including SNP arrays, allows us to detect and explore novel structure within specific cod management units. In Norwegian waters, coastal cod (i.e. those not undertaking extensive migrations) are divided into two arbitrary management units defined by ICES: one between 62° and 70°N (Norwegian coastal cod; NCC) and one between 58° and 62°N (Norwegian coastal south; NCS). Together, these capture a fishery area of >25,000 km2 containing many spawning grounds. To assess whether these geographic units correctly represent genetic stocks, we analysed spawning cod of NCC and NCS for more than 8,000 SNPs along with samples of Russian White Sea cod, north-east Arctic cod (NEAC: the largest Atlantic stock), and outgroup samples representing the Irish and Faroe Sea's. Our analyses revealed large differences in spatial patterns of genetic differentiation across the genome and revealed a complex biological structure within NCC and NCS. Haplotype maps from four chromosome sets show regional specific SNP indicating a complex genetic structure. The current management plan dividing the coastal cod into only two management units does not accurately reflect the genetic units and needs to be revised. Coastal cod in Norway, while highly heterogenous, is also genetically distinct from neighbouring stocks in the north (NEAC), west (Faroe Island) and the south. The White Sea cod are highly divergent from other cod, possibly yielding support to the earlier notion of subspecies rank.

10.
Evol Appl ; 13(8): 1906-1922, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32908594

RESUMO

Sustainable fisheries management requires detailed knowledge of population genetic structure. The European sprat is an important commercial fish distributed from Morocco to the Arctic circle, Baltic, Mediterranean, and Black seas. Prior to 2018, annual catch advice on sprat from the International Council for the Exploration of the Sea (ICES) was based on five putative stocks: (a) North Sea, (b) Kattegat-Skagerrak and Norwegian fjords, (c) Baltic Sea, (d) West of Scotland-southern Celtic Seas, and (e) English Channel. However, there were concerns that the sprat advice on stock size estimates management plan inadequately reflected the underlying biological units. Here, we used ddRAD sequencing to develop 91 SNPs that were thereafter used to genotype approximately 2,500 fish from 40 locations. Three highly distinct and relatively homogenous genetic groups were identified: (a) Norwegian fjords; (b) Northeast Atlantic including the North Sea, Kattegat-Skagerrak, Celtic Sea, and Bay of Biscay; and (c) Baltic Sea. Evidence of genetic admixture and possibly physical mixing was detected in samples collected from the transition zone between the North and Baltic seas, but not between any of the other groups. These results have already been implemented by ICES with the decision to merge the North Sea and the Kattegat-Skagerrak sprat to be assessed as a single unit, thus demonstrating that genetic data can be rapidly absorbed to align harvest regimes and biological units.

11.
Ecol Evol ; 10(12): 6120-6135, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32607218

RESUMO

Capture and long-distance translocation of cleaner fish to control lice infestations on marine salmonid farms has the potential to influence wild populations via overexploitation in source regions, and introgression in recipient regions. Knowledge of population genetic structure is therefore required. We studied the genetic structure of ballan wrasse, a phenotypically diverse and extensively used cleaner fish, from 18 locations in Norway and Sweden, and from Galicia, Spain, using 82 SNP markers. We detected two very distinct genetic groups in Scandinavia, northwestern and southeastern. These groups were split by a stretch of sandy beaches in southwest Norway, representing a habitat discontinuity for this rocky shore associated benthic egg-laying species. Wrasse from Galicia were highly differentiated from all Scandinavian locations, but more similar to northwestern than southeastern locations. Distinct genetic differences were observed between sympatric spotty and plain phenotypes in Galicia, but not in Scandinavia. The mechanisms underlying the geographic patterns between phenotypes are discussed, but not identified. We conclude that extensive aquaculture-mediated translocation of ballan wrasse from Sweden and southern Norway to western and middle Norway has the potential to mix genetically distinct populations. These results question the sustainability of the current cleaner fish practice.

12.
Ginecol. obstet. Méx ; 88(4): 252-260, ene. 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1346183

RESUMO

Resumen ANTECEDENTES: La neoplasia gestacional trofoblástica es un tumor raro, derivado de la gestación que procede de un desarrollo anormal del tejido trofoblástico. Incluye cuatro variedades, entre las que se encuentra la mola invasiva y el coriocarcinoma. Puede tener diferentes grados de proliferación; el diagnóstico diferencial es decisivo porque influye directamente en el tratamiento. Las molas premalignas suelen tratarse con legrado uterino, las malignas requieren tratamiento sistémico con mono o poliquimioterapia. CASO CLÍNICO: Paciente de 13 años, hospitalizada debido a un cuadro de vómitos y dolor abdominal. Durante el internamiento se le practicaron estudios complementarios: determinación de la fracción β de la gonadotropina coriónica humana (β-hCG) y tomografía axial computada para plantear el diagnóstico diferencial. El diagnóstico definitivo lo aportó la biopsia obtenida mediante legrado. El tratamiento se basó en la poliquimioterapia. En la actualidad está en remisión completa de la enfermedad. CONCLUSIONES: Resulta imprescindible detectar lo más temprano posible la gestación anómala, entender perfectamente su evolución e importancia de la anticoncepción mientras se trata y la enfermedad desaparece y minimizar la cantidad de pacientes que deben recibir quimioterapia.


Abstract BACKGROUND: Gestational trophoblastic neoplasia is a rare tumor that originates from pregnancy and it develop from anormal proliferation of trophoblastic tissue. It includes four varieties, including invasive mole and choriocarcinoma. They can present different degrees of proliferation, being essential differential diagnosis since it directly influences the treatment. Premalignant moles are usually treated by suction curettage while malignant forms require systemic therapy with mono or polychemotherapy. OBJECTIVE: Report the case, paying special attention to the differential diagnosis and treatment used, analyzing the reasons why polychemotherapy is established and describing the different possible options, based on current scientific evidence. CLINICAL CASE: We present the case of an invasive mola in a 13-year-old patient hospitalized by vomiting and abdominal pain. During this period, complementary techniques such as the determination of the β fraction of the human chorionic gonadotropin (β-hCG) or computed tomography (CT) are required to establish the differential diagnosis. Finally, the definitive diagnosis is provided by the biopsy obtained by curettage. Treatment is instituted with the pattern of polychemotherapy being, currently, with complete remission of the disease. CONCLUSIONS: Thus, it is essential to detect anomalous gestation early, to understand perfectly the evolution of this entity, the importance of contraception during its resolution, and to minimize patients susceptible to chemotherapy.

13.
Ginecol. obstet. Méx ; 88(8): 554-561, ene. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1346230

RESUMO

Resumen ANTECEDENTES: La incidencia de plasmocitoma extramedular es baja y su localización ginecológica es excepcional. Hasta la fecha se han reportado 27 casos de plasmocitomas ginecológicos (11 correspondientes a localización cervical). CASO CLÍNICO: Paciente de 37 años, sin antecedentes médicos de interés, que acudió a consulta por sangrado uterino anormal y postcoito. En la especuloscopia se apreció el cuello uterino hipertrófico y friable. Con la biopsia cervical se estableció el diagnóstico de plasmocitoma. Posteriormente, un estudio de extensión descartó la afectación en otras localizaciones. El tratamiento consistió en histerectomía y linfadenectomía pélvica, sin tratamiento coadyuvante. Los estudios de anatomía patológica e inmunohistoquímica confirmaron el diagnóstico. En la actualidad, la paciente se encuentra en seguimiento y libre de enfermedad. CONCLUSIONES: Debido a los pocos casos reportados de plasmocitoma cervical, no existe un tratamiento de referencia. A pesar de ello, no parece haber diferencias entre las pacientes tratadas con radioterapia o cirugía. La tasa de evolución a mieloma múltiple varía de 14 a 36%. La quimioterapia no disminuye la tasa de evolución a mieloma múltiple, por lo que está contraindicada.


Abstract BACKGROUND: The incidence of extramedullary plasmacytoma is low and, specifically, the gynecological location is exceptional. To date, 27 cases of gynecological plasmacytomas have been published (11 corresponding to cervical location). CLINICAL CASE: 37-year-old patient, with no relevant medical history, who came to a consultation for abnormal uterine bleeding and bleeding. By spectroscopy, the hypertrophic and friable cervix was appreciated. Cervical biopsy verifies the diagnosis of plasmacytoma. Subsequently, an extension study ruled out involvement in other locations. Treatment consists of hysterectomy and pelvic lymphadenectomy, without adjuvant chemotherapy. The pathological and immunohistochemical studies confirmed the diagnosis. Currently, the patient is in follow-up and free of disease. CONCLUSIONS: Due to the scarcity of published cases of cervical plasmacytoma, there is no reference treatment. Despite this, there do not appear to be any differences between the patients treated with radiotherapy or surgery. The rate of progression to multiple myeloma varies from 14-36%. The adjuvant therapy does not change the rate of progression to multiple myeloma, so it is contraindicated.

14.
Ecol Evol ; 9(12): 6901-6921, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31380023

RESUMO

Atlantic salmon is characterized by a high degree of population genetic structure throughout its native range. However, while populations inhabiting rivers in Norway and Russia make up a significant proportion of salmon in the Atlantic, thus far, genetic studies in this region have only encompassed low to modest numbers of populations. Here, we provide the first "in-depth" investigation of population genetic structuring in the species in this region. Analysis of 18 microsatellites on >9,000 fish from 115 rivers revealed highly significant population genetic structure throughout, following a hierarchical pattern. The highest and clearest level of division separated populations north and south of the Lofoten region in northern Norway. In this region, only a few populations displayed intermediate genetic profiles, strongly indicating a geographically limited transition zone. This was further supported by a dedicated cline analysis. Population genetic structure was also characterized by a pattern of isolation by distance. A decline in overall genetic diversity was observed from the south to the north, and two of the microsatellites showed a clear decrease in number of alleles across the observed transition zone. Together, these analyses support results from previous studies, that salmon in Norway originate from two main genetic lineages, one from the Barents-White Sea refugium that recolonized northern Norwegian and adjacent Russian rivers, and one from the eastern Atlantic that recolonized the rest of Norway. Furthermore, our results indicate that local conditions in the limited geographic transition zone between the two observed lineages, characterized by open coastline with no obvious barriers to gene flow, are strong enough to maintain the genetic differentiation between them.

15.
Mol Ecol ; 28(11): 2786-2801, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31067349

RESUMO

Ectotherm development rates often show adaptive divergence along climatic gradients, but the genetic basis for this variation is rarely studied. Here, we investigated the genetic basis for phenotypic variation in larval development in the moor frog Rana arvalis from five regions along a latitudinal gradient from Germany to northern Sweden. We focused on the C/EBP-1 gene, a transcription factor associated with larval development time. Allele frequencies at C/EBP-1 varied strongly among geographical regions. Overall, the distribution of alleles along the gradient was in concordance with the dual post-glacial colonization routes into Scandinavia, with a large number of alleles exclusively present along the southern colonization route. Only three of 38 alleles were shared between the routes. Analysis of contemporary selection on C/EBP-1 showed divergent selection among the regions, probably reflecting adaptation to the local environmental conditions, although this was especially strong between southern and northern regions coinciding also with lineages from different colonization routes. Overall, the C/EBP-1 gene has historically been under purifying selection, but two specific amino acid positions showed significant signals of positive selection. These positions showed divergence between southern and northern regions, and we suggest that they are functionally involved in the climatic adaptation of larval development. Using phenotypic data from a common garden experiment, we found evidence for specific C/EBP-1 alleles being correlated with larval development time, suggesting a functional role in adaptation of larval development to large-scale climatic variation.


Assuntos
Variação Genética , Geografia , Ranidae/crescimento & desenvolvimento , Ranidae/genética , Seleção Genética , Fatores de Transcrição/metabolismo , Alelos , Animais , Códon/genética , Frequência do Gene/genética , Estudos de Associação Genética , Larva/genética , Larva/crescimento & desenvolvimento , Modelos Lineares , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
16.
Sensors (Basel) ; 18(11)2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30360483

RESUMO

The spectral narrowing of Fiber Bragg Gratings (FBGs) introduced by unpumped Er-doped fiber (EDF) was analyzed for fiber lasers (FL). Owing to spatial hole burning (SHB), the spectral response of a virtual FBG can be employed for narrowing the band pass filter employed to determine the lasing wavelength of laser cavities. A common FL was mounted to analyze the spectral stability of the method, and a FL sensor for strain and temperature measurements was experimentally characterized to determine the stability of the narrowing effect achieved by the unpumped EDF, which acts as a virtual FBG. The results exhibited remarkably good narrowing effects of the spectral response of uniform FBGs.

17.
BMC Genet ; 19(1): 42, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29986643

RESUMO

BACKGROUND: Atlantic cod (Gadus morhua L.) has formed the basis of many economically significant fisheries in the North Atlantic, and is one of the best studied marine fishes, but a legacy of overexploitation has depleted populations and collapsed fisheries in several regions. Previous studies have identified considerable population genetic structure for Atlantic cod. However, within Norway, which is the country with the largest remaining catch in the Atlantic, the population genetic structure of coastal cod (NCC) along the entire coastline has not yet been investigated. We sampled > 4000 cod from 55 spawning sites. All fish were genotyped with 6 microsatellite markers and Pan I (Dataset 1). A sub-set of the samples (1295 fish from 17 locations) were also genotyped with an additional 9 microsatellites (Dataset 2). Otoliths were read in order to exclude North East Arctic Cod (NEAC) from the analyses, as and where appropriate. RESULTS: We found no difference in genetic diversity, measured as number of alleles, allelic richness, heterozygosity nor effective population sizes, in the north-south gradient. In both data sets, weak but significant population genetic structure was revealed (Dataset 1: global FST = 0.008, P < 0.0001. Dataset 2: global FST = 0.004, P < 0.0001). While no clear genetic groups were identified, genetic differentiation increased among geographically-distinct samples. Although the locus Gmo132 was identified as a candidate for positive selection, possibly through linkage with a genomic region under selection, overall trends remained when this locus was excluded from the analyses. The most common allele in loci Gmo132 and Gmo34 showed a marked frequency change in the north-south gradient, increasing towards the frequency observed in NEAC in the north. CONCLUSION: We conclude that Norwegian coastal cod displays significant population genetic structure throughout its entire range, that follows a trend of isolation by distance. Furthermore, we suggest that a gradient of genetic introgression between NEAC and NCC contributes to the observed population genetic structure. The current management regime for coastal cod in Norway, dividing it into two stocks at 62°N, represents a simplification of the level of genetic connectivity among coastal cod in Norway, and needs revision.


Assuntos
Gadus morhua/genética , Animais , Aquicultura , Genômica , Genótipo , Técnicas de Genotipagem , Repetições de Microssatélites/genética , Noruega , Membrana dos Otólitos/anatomia & histologia , População/genética , Seleção Genética
18.
Evol Appl ; 10(10): 1007-1019, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29151856

RESUMO

The salmon louse is a highly abundant ectoparasitic copepod of salmonids in the North Pacific and Atlantic. Widespread and rapid development of resistance to chemical agents used to delouse salmonids on marine farms is now threatening the continued development of the aquaculture industry and have served as a potent catalyst for the development of alternative pest management strategies. These include freshwater and warm-water treatments to which the louse is sensitive. However, given the well-documented evolutionary capacity of this species, the risk of developing tolerance towards these environmental treatments cannot be dismissed. Two common-garden experiments were performed using full-sibling families of lice identified by DNA parentage testing to investigate whether one of the fundamental premises for evolution, in this context genetic variation in the capacity of coping with fresh or warm water, exists within this species. Significant differences in survival were observed among families in both experiments, although for the salinity experiment, it was not possible to unequivocally disentangle background mortality from treatment-induced mortality. Thus, our data demonstrate genetic variation in tolerance of warm water and are suggestive of genetic variation in salinity tolerance. We conclude that extensive use of these environmental-based treatments to delouse salmonids on commercial farms may drive lice towards increased tolerance.

19.
Adv Mind Body Med ; 31(1): 14-17, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28183073

RESUMO

Context • The Melkersson-Rosenthal syndrome (MRS) is a rare condition characterized by a triad of symptoms: (1) recurrent and/or persistent orofacial swelling, (2) recurrent facial paralysis, and (3) a fissured tongue. Although various contributing factors have been suggested, the etiology and mechanisms of the syndrome have not been fully elucidated. Objective • The aim of the current study was to examine for the first time some psychosomatic aspects of the syndrome and to evaluate the benefits of a brief psychotherapeutic process in which the research team worked to reintegrate the complex bio-psycho-social functioning of the patient. Design • The research team performed a case study. Setting • The study took place at the outpatient clinic for psychiatric services of the Alto Minho Local Health Unit (Viana do Castelo, Portugal). Participant • The participant was a 26-y-old woman suffering from MRS who received services at the clinic for depression. Her clinical history revealed that significant life events had acted as triggers for her syndrome, both at the start and during several exacerbations of her symptoms. Intervention • The intervention consisted of 15 weekly sessions focused on insight promotion. Outcome Measures • The case study measured changes in the patient's condition through her verbal self-reports about her physical and mental state, and the research team's clinical evaluation. Results • The treatment allowed remission of her depression and diminished the frequency of her relapses of MRS. Conclusions • The current case study offers the first report that describes how significant affective phenomena can act as triggers in the MRS. It also opens the possibility of providing psychiatric and psychological therapeutic interventions to help prevent relapses and exacerbations of that syndrome.


Assuntos
Síndrome de Melkersson-Rosenthal , Adulto , Paralisia Facial , Feminino , Humanos , Lábio/patologia , Transtornos Psicofisiológicos , Língua/patologia
20.
BMC Genomics ; 18(1): 76, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086785

RESUMO

BACKGROUND: In the marine environment, where there are few absolute physical barriers, contemporary contact between previously isolated species can occur across great distances, and in some cases, may be inter-oceanic. An example of this can be seen in the minke whale species complex. Antarctic minke whales are genetically and morphologically distinct from the common minke found in the north Atlantic and Pacific oceans, and the two species are estimated to have been isolated from each other for 5 million years or more. Recent atypical migrations from the southern to the northern hemisphere have been documented and fertile hybrids and back-crossed individuals between both species have also been identified. However, it is not known whether this represents a contemporary event, potentially driven by ecosystem changes in the Antarctic, or a sporadic occurrence happening over an evolutionary time-scale. We successfully used whole genome resequencing to identify a panel of diagnostic SNPs which now enable us address this evolutionary question. RESULTS: A large number of SNPs displaying fixed or nearly fixed allele frequency differences among the minke whale species were identified from the sequence data. Five panels of putatively diagnostic markers were established on a genotyping platform for validation of allele frequencies; two panels (26 and 24 SNPs) separating the two species of minke whale, and three panels (22, 23, and 24 SNPs) differentiating the three subspecies of common minke whale. The panels were validated against a set of reference samples, demonstrating the ability to accurately identify back-crossed whales up to three generations. CONCLUSIONS: This work has resulted in the development of a panel of novel diagnostic genetic markers to address inter-oceanic and global contact among the genetically isolated minke whale species and sub-species. These markers, including a globally relevant genetic reference data set for this species complex, are now openly available for researchers interested in identifying other potential whale hybrids in the world's oceans. The approach used here, combining whole genome resequencing and high-throughput genotyping, represents a universal approach to develop similar tools for other species and population complexes.


Assuntos
Migração Animal , Marcadores Genéticos , Genoma , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Hibridização Genética , Baleia Anã/genética , Alelos , Animais , Mapeamento Cromossômico , Cruzamentos Genéticos , Frequência do Gene , Genética Populacional , Genômica/métodos , Genótipo , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Reprodutibilidade dos Testes
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