scholarly journals Patterns of genetic connectivity in deep-sea vulnerable marine ecosystems and implications for conservation

2021 ◽  
Author(s):  
◽  
Cong Zeng
Keyword(s):  
Gene Flow ◽  
New Zealand ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Deep Sea ◽  
Population Genetic ◽  
Genetic Connectivity ◽  
North Central ◽  
Indicator Taxa ◽  
Central South

<p>Knowledge about and understanding of population structure and connectivity of deep-sea fauna decreases with increasing depth, but such information is crucial for the management of vulnerable marine ecosystems (VMEs) in particular. As such, research using genetic markers, which does not require knowledge of ecological or environmental processes as a prerequisite for the analysis, is a practical method to investigate population connectivity of VME indicator taxa. However, population genetics studies are yet to be broadly conducted in the deep sea around New Zealand.  To provide background information and develop hypothesises for this research, 196 population genetic studies of deep-sea fauna were reviewed and analysed. Based on the collected studies, four different patterns of spatial genetic structure were observed: global homogeneous, oceanic, regional, and fine structure. These different structures were reported that they were related to depth, topography, distance between populations, temperature and other biological factors. Quantification of the relationship between these factors and the detection of barriers to gene flow (barrier detection) showed that depth, currents and topography contributed significantly to barrier detection and depth and topography were acting as a barrier to gene flow in the deep sea. Furthermore, different sampling strategies and different genetic marker types significantly influenced genetic barrier detection. Comparison amongst different habitats suggested that different conservation strategies should be developed for different habitat types (Chapter 2).  This study used different genetic markers to assess the genetic connectivity amongst VME indicator taxa Vulnerable Marine Ecosystems (VME). Seven VME indicator taxa were selected: 4 sponges (Neoaulaxinia persicum, Penares sp., Pleroma menoui and Poecillastra laminaris) and 3 corals (Goniocorella dumosa, Madrepora oculata and Solenosmilia variabilis), at different spatial scales. Due to lack of genetic information for these species, genetic markers were developed for Poecillastra laminaris (0) and S. variabilis (Chapter 4).  A geographic province (northern-southern province), region (north-central-south), and geomorphic feature hierarchical testing framework was employed to examine species-specific genetic variation in mitochondrial (COI, Cytb and 12S) and nuclear markers (microsatellites) amongst populations of four deep-sea sponges within the New Zealand region. For Poecillastra laminaris, significant mitochondrial and nuclear DNA genetic differences were revealed amongst biogeographic provinces. In contrast, no significant structure was detected across the same area for Penares sp. Both Neoaulaxinia persicum and Pleroma menoui were only available from the northern province, in which Pleroma menoui showed no evidence of genetic structure, but N. persicum exhibited a geographic differentiation in 12S. No depthrelated isolation was observed for any of the four species at the mitochondrial markers, nor at the microsatellite loci for Poecillastra laminaris. Genetic connectivity in Poecillastra laminaris is likely to be influenced by oceanic sub-surface currents that generate routes for gene flow and may also act as barriers to dispersal. Although data are limited, these results suggest that the differences in patterns of genetic structure amongst the species can be attributed to differences in life history and reproductive strategies. The results are discussed in the context of existing marine protected areas, and the future design of spatial management measures for protecting VMEs in the New Zealand region (Chapter 5).  To better understand the vulnerability of stony corals (Goniocorella dumosa, Madrepora oculata and Solenosmilia variabilis) to disturbance within the New Zealand region, and to guide marine protected area design, genetic structure and connectivity were determined using microsatellite loci and DNA sequencing. Analyses compared population genetic differentiation between two biogeographic provinces, amongst three sub-regions (north-central-south), and amongst geomorphic features. Population genetic differentiation varied amongst species and between marker types. For G. dumosa, genetic differentiation existed amongst regions and populations on geomorphic features, but not between provinces. For M. oculata, only a north-central-south regional structure was observed. For S. variabilis, genetic differentiation was observed between provinces, amongst regions and amongst geomorphic features based on microsatellite variation. Multivariate analyses indicated that populations on the Kermadec Ridge were genetically different from Chatham Rise populations in all three coral species. Furthermore, a significant isolation-by-depth pattern was observed for both marker types in G. dumosa, and also in ITS of M. oculata. An isolation-by-distance pattern was found in microsatellites of S. variabilis. Migrate analysis showed that medium to high self-recruitment were detected in all geomorphic feature populations, and different species presented different genetic connectivity patterns. These different patterns of population genetic structure and connectivity at a range of spatial scales indicate that flexible spatial management is required for the conservation of deep-sea corals around New Zealand (Chapter 6).  Understanding the deep-sea ecological processes that shape spatial genetic patterns of species is critical for predicting evolutionary dynamics and defining significant evolutionary and/or management units. In this study, the potential role of environmental factors in shaping the genetic structure of the 7 deep-sea habit-providing study species was investigated using a seascape genetics approach. The genetic data were acquired from nuclear and mitochondrial sequences and microsatellite genotype data, and 25 environmental variables (5 topographic, 17 physiochemical and 3 biological variables). The results indicated that environmental factors affected genetic variation differently amongst the species. However, factors related to current and food source explained the north-central-south genetic structure in sponges and corals, and environmental variation in these parameters may be acting as a barrier to gene flow. At the geomorphic feature level, the DistLM and dbRDA analysis showed that factors related to the food source and topography were most related to genetic variation in microsatellites of sponge and corals. This study highlights the utility of seascape genetic studies to better understand the processes shaping the genetic structure of organisms (Chapter 7).  The outcomes of this study provide vital information to assist in effective management and conservation of VME indicator taxa and contribute to an understanding of evolutionary and ecological processes in the deep sea (Chapter 8).</p>

scholarly journals Patterns of genetic connectivity in deep-sea vulnerable marine ecosystems and implications for conservation

2021 ◽  
Author(s):  
◽  
Cong Zeng
Keyword(s):  
Gene Flow ◽  
New Zealand ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Deep Sea ◽  
Population Genetic ◽  
Genetic Connectivity ◽  
North Central ◽  
Indicator Taxa ◽  
Central South

<p>Knowledge about and understanding of population structure and connectivity of deep-sea fauna decreases with increasing depth, but such information is crucial for the management of vulnerable marine ecosystems (VMEs) in particular. As such, research using genetic markers, which does not require knowledge of ecological or environmental processes as a prerequisite for the analysis, is a practical method to investigate population connectivity of VME indicator taxa. However, population genetics studies are yet to be broadly conducted in the deep sea around New Zealand.  To provide background information and develop hypothesises for this research, 196 population genetic studies of deep-sea fauna were reviewed and analysed. Based on the collected studies, four different patterns of spatial genetic structure were observed: global homogeneous, oceanic, regional, and fine structure. These different structures were reported that they were related to depth, topography, distance between populations, temperature and other biological factors. Quantification of the relationship between these factors and the detection of barriers to gene flow (barrier detection) showed that depth, currents and topography contributed significantly to barrier detection and depth and topography were acting as a barrier to gene flow in the deep sea. Furthermore, different sampling strategies and different genetic marker types significantly influenced genetic barrier detection. Comparison amongst different habitats suggested that different conservation strategies should be developed for different habitat types (Chapter 2).  This study used different genetic markers to assess the genetic connectivity amongst VME indicator taxa Vulnerable Marine Ecosystems (VME). Seven VME indicator taxa were selected: 4 sponges (Neoaulaxinia persicum, Penares sp., Pleroma menoui and Poecillastra laminaris) and 3 corals (Goniocorella dumosa, Madrepora oculata and Solenosmilia variabilis), at different spatial scales. Due to lack of genetic information for these species, genetic markers were developed for Poecillastra laminaris (0) and S. variabilis (Chapter 4).  A geographic province (northern-southern province), region (north-central-south), and geomorphic feature hierarchical testing framework was employed to examine species-specific genetic variation in mitochondrial (COI, Cytb and 12S) and nuclear markers (microsatellites) amongst populations of four deep-sea sponges within the New Zealand region. For Poecillastra laminaris, significant mitochondrial and nuclear DNA genetic differences were revealed amongst biogeographic provinces. In contrast, no significant structure was detected across the same area for Penares sp. Both Neoaulaxinia persicum and Pleroma menoui were only available from the northern province, in which Pleroma menoui showed no evidence of genetic structure, but N. persicum exhibited a geographic differentiation in 12S. No depthrelated isolation was observed for any of the four species at the mitochondrial markers, nor at the microsatellite loci for Poecillastra laminaris. Genetic connectivity in Poecillastra laminaris is likely to be influenced by oceanic sub-surface currents that generate routes for gene flow and may also act as barriers to dispersal. Although data are limited, these results suggest that the differences in patterns of genetic structure amongst the species can be attributed to differences in life history and reproductive strategies. The results are discussed in the context of existing marine protected areas, and the future design of spatial management measures for protecting VMEs in the New Zealand region (Chapter 5).  To better understand the vulnerability of stony corals (Goniocorella dumosa, Madrepora oculata and Solenosmilia variabilis) to disturbance within the New Zealand region, and to guide marine protected area design, genetic structure and connectivity were determined using microsatellite loci and DNA sequencing. Analyses compared population genetic differentiation between two biogeographic provinces, amongst three sub-regions (north-central-south), and amongst geomorphic features. Population genetic differentiation varied amongst species and between marker types. For G. dumosa, genetic differentiation existed amongst regions and populations on geomorphic features, but not between provinces. For M. oculata, only a north-central-south regional structure was observed. For S. variabilis, genetic differentiation was observed between provinces, amongst regions and amongst geomorphic features based on microsatellite variation. Multivariate analyses indicated that populations on the Kermadec Ridge were genetically different from Chatham Rise populations in all three coral species. Furthermore, a significant isolation-by-depth pattern was observed for both marker types in G. dumosa, and also in ITS of M. oculata. An isolation-by-distance pattern was found in microsatellites of S. variabilis. Migrate analysis showed that medium to high self-recruitment were detected in all geomorphic feature populations, and different species presented different genetic connectivity patterns. These different patterns of population genetic structure and connectivity at a range of spatial scales indicate that flexible spatial management is required for the conservation of deep-sea corals around New Zealand (Chapter 6).  Understanding the deep-sea ecological processes that shape spatial genetic patterns of species is critical for predicting evolutionary dynamics and defining significant evolutionary and/or management units. In this study, the potential role of environmental factors in shaping the genetic structure of the 7 deep-sea habit-providing study species was investigated using a seascape genetics approach. The genetic data were acquired from nuclear and mitochondrial sequences and microsatellite genotype data, and 25 environmental variables (5 topographic, 17 physiochemical and 3 biological variables). The results indicated that environmental factors affected genetic variation differently amongst the species. However, factors related to current and food source explained the north-central-south genetic structure in sponges and corals, and environmental variation in these parameters may be acting as a barrier to gene flow. At the geomorphic feature level, the DistLM and dbRDA analysis showed that factors related to the food source and topography were most related to genetic variation in microsatellites of sponge and corals. This study highlights the utility of seascape genetic studies to better understand the processes shaping the genetic structure of organisms (Chapter 7).  The outcomes of this study provide vital information to assist in effective management and conservation of VME indicator taxa and contribute to an understanding of evolutionary and ecological processes in the deep sea (Chapter 8).</p>

scholarly journals Population genetic structure of New Zealand blue cod (Parapercis colias) based on mitochondrial and microsatellite DNA markers

2021 ◽  
Author(s):  
◽  
Clare Louise Gebbie
Keyword(s):  
New Zealand ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Dna Markers ◽  
Microsatellite Dna ◽  
Population Genetic ◽  
Current Knowledge ◽  
Isolation By Distance ◽  
Genetic Connectivity ◽  
Microsatellite Dna Markers

<p>Parapercis colias (blue cod) is an endemic temperate reef fish that supports an important commercial and recreational fishery in New Zealand. However, concerns have been raised about localized stock depletion, and multiple lines of evidence have suggested P. colias may form several biologically distinct populations within the New Zealand Exclusive Economic Zone. Mark and recapture studies along with otolith and stable isotope studies have indicated that individuals are sedentary with very limited movement beyond the scale of 10-20km. The primary goal of this research was to advance the current knowledge of P. colias population genetic structure. This information can be incorporated into stock assessment models with the aim of improving the management of the P. colias fishery. This study made use of 454 pyrosequencing technology to isolate and develop the first set of microsatellite DNA markers for P. colias. These seven microsatellite loci, along with mitochondrial control region sequences, were used to determine the levels of genetic variation and differentiation between sites around the New Zealand coastline, including the Chatham Islands.  Significant differentiation was observed between the Chatham Islands and mainland New Zealand sample sites, indicating that these two regions form distinct populations. Interpretation of the results for the mainland sites was more complex. Mitochondrial sequence data detected no significant pairwise differentiation between mainland sites, although a pattern of isolation-by-distance was observed. However, evidence for genetic differentiation among mainland sites was weak based on the microsatellite DNA analysis. Although pairwise Gѕт levels were significant in some sites, this was not reflected in principal component analysis or Bayesian structure analysis. It is likely that through long range dispersal, migration is at or above the threshold for genetic connectivity, but below a level necessary for demographic connectivity. This is indicated by both the genetic structure reported here, along with previous studies showing limited dispersal of P. colias.</p>

Microsatellite analysis of North American pine marten (Martes americana) populations from the Yukon and Northwest Territories

2000 ◽  
Vol 78 (7) ◽  
pp. 1150-1157 ◽  
Author(s):  
C J Kyle ◽  
C S Davis ◽  
C Strobeck
Keyword(s):  
Population Structure ◽  
Gene Flow ◽  
Genetic Structure ◽  
Northwest Territories ◽  
Population Genetic Structure ◽  
North American ◽  
Population Genetic ◽  
Martes Americana ◽  
Genetic Connectivity ◽  
Pine Marten

Elucidating the population genetic structure of a species gives us insight into the levels of gene flow between geographic regions. Such data may have important implications for those trying to manage a heavily harvested wildlife species by determining the genetic connectivity of adjacent populations. In this study, the population structure of 12 North American pine marten (Martes americana) populations from the Yukon through to the central Northwest Territories was investigated using 11 microsatellite loci. Genetic variation within populations across the entire geographic range was relatively homogeneous as measured by: mean number of alleles (5.89 ± 0.45) and the average unbiased expected heterozygosity (He) (65.6 ± 1.7%). The overall unbiased probability of identity showed more variance between populations (1/10.25 ± 7.84 billion) than did the mean number of alleles and the He estimates. Although some population structure was found among the populations, most regions were not strongly differentiated from one another. The low level of structure among the populations can, in part, be attributed to isolation by distance rather than to population fragmentation, as would be expected in more southerly regions in which suitable habitat is more disjunct. Furthermore, the low levels of population genetic structure were likely due to high levels of gene flow between regions and to large effective marten populations in the northern part of their distribution.

scholarly journals Population genetic structure and connectivity patterns of the kanae (Mugil cephalus) in New Zealand inland and coastal waters

2021 ◽  
Author(s):  
◽  
Angel Jimenez Brito
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
New Zealand ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Coastal Waters ◽  
Population Genetic ◽  
Mugil Cephalus ◽  
Connectivity Patterns

<p>Mugil cephalus is a cosmopolitan fish species found in most coastal waters from tropical to temperate zones. It is a species common in the near-shore marine environment, and known to reside in estuarine and freshwater systems. Adult M. cephalus move out to sea to spawn in aggregations. Their larvae can drift on surface ocean currents for over a month before recruitment to nursery grounds. Mugil cephalus is a species that is closely associated with the coastal environment, but it is capable of interoceanic migrations. Population genetic studies have reported high levels of genetic differentiation among populations in the Mediterranean, Atlantic and western Pacific. However, there is no evidence to suggest reproductive incompatibility has arisen among populations. In New Zealand M. cephalus supports important recreational, commercial and customary fisheries, but very little is known about the distribution and connectivity among populations.  The aim of this study was to use nuclear microsatellite DNA (msatDNA) and mitochondrial DNA (mtDNA) markers to describe the population genetic structure, connectivity patterns and to determine the phylogeographic history of New Zealand M. cephalus populations. Total of 850 samples were collected (576 adults and 274 juveniles) during the summers of 2010 and 2014-2015 from 15 locations around coastal and inland waters of the North Island, and one location in Marlborough Sounds. In addition, 245 mtDNA sequences were added from previously published studies and used to outgroup the New Zealand population and place it into the context of the other Pacific populations.  Seven msatDNA loci were isolated and used to determine the population genetic structure and connectivity patterns of M. cephalus in New Zealand. Admixture of four genetically distinct groups or populations was identified and a chaotic spatial distribution of allele frequencies. Within each population there was significant gene flow among locations, no pattern of genetic isolation-by-distance was identified and there was a high proportion of non-migrant individuals. There was evidence of bottlenecks and seasonal reproductive variation of adults, which could explain the significant shifts in the effective population size among locations.  To test whether the pattern of genetic variation in M. cephalus populations was the result of seasonal variability in the reproductive success of adults, DNA from adult and juvenile samples were used to test for differences in the levels of genetic variation between generations (cohorts). Juveniles were grouped by age classes and compared to the adults. The levels of genetic diversity within the groups of juveniles were compared to the adult population and significant genetic bottlenecks between juveniles and adults were detected. This pattern was consistent with the Sweepstake-Reproductive-Success hypothesis. Two spawning groups in the adults were identified, an early spawning group and a late spawning group.  The analysis of DNA sequence data from the mtDNA Cytochrome Oxidase subunit 1 (COX1) gene and D-loop region showed two sympatric haplogroups of M. cephalus. New Zealand was most likely colonised by M. cephalus migrants from different population sources from the Pacific first ~50,000 and a second wave of migrants from Australia between ~20, 000 and ~16,000 years ago. High levels of gene flow were detected, but there has not been enough time for genetic drift to completely sort the lineages.  The findings of this thesis research will help with the understanding of aspects of M. cephalus dispersal and the genetic structure of populations. The patterns of connectivity can be used to better align the natural boundaries of wild populations to the fishery management stock structure. Understanding the reproductive units, levels of genetic diversity and the patterns of reproduction of M. cephalus will assist management efforts to focus on the key habitats threats, risks and the long-term sustainability of the species.</p>

scholarly journals Population genetic structure and connectivity patterns of the kanae (Mugil cephalus) in New Zealand inland and coastal waters

2021 ◽  
Author(s):  
◽  
Angel Jimenez Brito
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
New Zealand ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Coastal Waters ◽  
Population Genetic ◽  
Mugil Cephalus ◽  
Connectivity Patterns

<p>Mugil cephalus is a cosmopolitan fish species found in most coastal waters from tropical to temperate zones. It is a species common in the near-shore marine environment, and known to reside in estuarine and freshwater systems. Adult M. cephalus move out to sea to spawn in aggregations. Their larvae can drift on surface ocean currents for over a month before recruitment to nursery grounds. Mugil cephalus is a species that is closely associated with the coastal environment, but it is capable of interoceanic migrations. Population genetic studies have reported high levels of genetic differentiation among populations in the Mediterranean, Atlantic and western Pacific. However, there is no evidence to suggest reproductive incompatibility has arisen among populations. In New Zealand M. cephalus supports important recreational, commercial and customary fisheries, but very little is known about the distribution and connectivity among populations.  The aim of this study was to use nuclear microsatellite DNA (msatDNA) and mitochondrial DNA (mtDNA) markers to describe the population genetic structure, connectivity patterns and to determine the phylogeographic history of New Zealand M. cephalus populations. Total of 850 samples were collected (576 adults and 274 juveniles) during the summers of 2010 and 2014-2015 from 15 locations around coastal and inland waters of the North Island, and one location in Marlborough Sounds. In addition, 245 mtDNA sequences were added from previously published studies and used to outgroup the New Zealand population and place it into the context of the other Pacific populations.  Seven msatDNA loci were isolated and used to determine the population genetic structure and connectivity patterns of M. cephalus in New Zealand. Admixture of four genetically distinct groups or populations was identified and a chaotic spatial distribution of allele frequencies. Within each population there was significant gene flow among locations, no pattern of genetic isolation-by-distance was identified and there was a high proportion of non-migrant individuals. There was evidence of bottlenecks and seasonal reproductive variation of adults, which could explain the significant shifts in the effective population size among locations.  To test whether the pattern of genetic variation in M. cephalus populations was the result of seasonal variability in the reproductive success of adults, DNA from adult and juvenile samples were used to test for differences in the levels of genetic variation between generations (cohorts). Juveniles were grouped by age classes and compared to the adults. The levels of genetic diversity within the groups of juveniles were compared to the adult population and significant genetic bottlenecks between juveniles and adults were detected. This pattern was consistent with the Sweepstake-Reproductive-Success hypothesis. Two spawning groups in the adults were identified, an early spawning group and a late spawning group.  The analysis of DNA sequence data from the mtDNA Cytochrome Oxidase subunit 1 (COX1) gene and D-loop region showed two sympatric haplogroups of M. cephalus. New Zealand was most likely colonised by M. cephalus migrants from different population sources from the Pacific first ~50,000 and a second wave of migrants from Australia between ~20, 000 and ~16,000 years ago. High levels of gene flow were detected, but there has not been enough time for genetic drift to completely sort the lineages.  The findings of this thesis research will help with the understanding of aspects of M. cephalus dispersal and the genetic structure of populations. The patterns of connectivity can be used to better align the natural boundaries of wild populations to the fishery management stock structure. Understanding the reproductive units, levels of genetic diversity and the patterns of reproduction of M. cephalus will assist management efforts to focus on the key habitats threats, risks and the long-term sustainability of the species.</p>

Genetic diversity and population structure of Korean alder (Alnus japonica; Betulaceae)

1999 ◽  
Vol 29 (9) ◽  
pp. 1311-1316 ◽  
Author(s):  
Man Kyu Huh
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Gene Flow ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Population Genetic ◽  
Alnus Japonica ◽  
Alnus Crispa ◽  
The Mean ◽  
Fixation Indices

The genetic diversity and population genetic structure of Alnus japonica (Thunb.) Steudel in Korea were studied and compared with those of alder from Canada. Nineteen of the 25 loci studied (76.0%) showed detectable polymorphism. The mean genetic diversity within populations was 0.207, which was higher than that for two Canadian alder species (Alnus rugosa (Du Roi) Spreng. and Alnus crispa (Ait.) Pursh). Analysis of fixation indices, calculated for all polymorphic loci in each population, showed a substantial deficiency of heterozygotes relative to Hardy-Weinberg expectations. The mean population differentiation value of A. japonica in Korea (GST = 0.095) is similar to those of A. rugosa in Canada (GST = 0.052). These low values of GST in two countries, reflecting little spatial genetic differentiation, may indicate extensive gene flow (via pollen and (or) seeds) and (or) recent colonization.

scholarly journals Patterns of spatial genetic structures in Aedes albopictus (Diptera: Culicidae) populations in China

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Yong Wei ◽  
Jiatian Wang ◽  
Zhangyao Song ◽  
Yulan He ◽  
Zihao Zheng ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Gene Flow ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Population Genetic ◽  
Spatial Genetic Structure ◽  
Vector Borne Diseases ◽  
Vector Borne ◽  
Genetic Structures

Abstract Background The Asian tiger mosquito, Aedes albopictus, is one of the 100 worst invasive species in the world and the vector for several arboviruses including dengue, Zika and chikungunya viruses. Understanding the population spatial genetic structure, migration, and gene flow of vector species is critical to effectively preventing and controlling vector-borne diseases. Little is known about the population structure and genetic differentiation of native Ae. albopictus in China. The aim of this study was to examine the patterns of the spatial genetic structures of native Ae. albopictus populations, and their relationship to dengue incidence, on a large geographical scale. Methods During 2016–2018, adult female Ae. albopictus mosquitoes were collected by human landing catch (HLC) or human-bait sweep-net collections in 34 localities across China. Thirteen microsatellite markers were used to examine the patterns of genetic diversity, population structure, and gene flow among native Ae. albopictus populations. The correlation between population genetic indices and dengue incidence was also examined. Results A total of 153 distinct alleles were identified at the 13 microsatellite loci in the tested populations. All loci were polymorphic, with the number of distinct alleles ranging from eight to sixteen. Genetic parameters such as PIC, heterozygosity, allelic richness and fixation index (FST) revealed highly polymorphic markers, high genetic diversity, and low population genetic differentiation. In addition, Bayesian analysis of population structure showed two distinct genetic groups in southern-western and eastern-central-northern China. The Mantel test indicated a positive correlation between genetic distance and geographical distance (R2 = 0.245, P = 0.01). STRUCTURE analysis, PCoA and GLS interpolation analysis indicated that Ae. albopictus populations in China were regionally clustered. Gene flow and relatedness estimates were generally high between populations. We observed no correlation between population genetic indices of microsatellite loci in Ae. albopictus populations and dengue incidence. Conclusion Strong gene flow probably assisted by human activities inhibited population differentiation and promoted genetic diversity among populations of Ae. albopictus. This may represent a potential risk of rapid spread of mosquito-borne diseases. The spatial genetic structure, coupled with the association between genetic indices and dengue incidence, may have important implications for understanding the epidemiology, prevention, and control of vector-borne diseases.

scholarly journals Population genetic structure of New Zealand blue cod (Parapercis colias) based on mitochondrial and microsatellite DNA markers

2021 ◽  
Author(s):  
◽  
Clare Louise Gebbie
Keyword(s):  
New Zealand ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Dna Markers ◽  
Microsatellite Dna ◽  
Population Genetic ◽  
Current Knowledge ◽  
Isolation By Distance ◽  
Genetic Connectivity ◽  
Microsatellite Dna Markers

<p>Parapercis colias (blue cod) is an endemic temperate reef fish that supports an important commercial and recreational fishery in New Zealand. However, concerns have been raised about localized stock depletion, and multiple lines of evidence have suggested P. colias may form several biologically distinct populations within the New Zealand Exclusive Economic Zone. Mark and recapture studies along with otolith and stable isotope studies have indicated that individuals are sedentary with very limited movement beyond the scale of 10-20km. The primary goal of this research was to advance the current knowledge of P. colias population genetic structure. This information can be incorporated into stock assessment models with the aim of improving the management of the P. colias fishery. This study made use of 454 pyrosequencing technology to isolate and develop the first set of microsatellite DNA markers for P. colias. These seven microsatellite loci, along with mitochondrial control region sequences, were used to determine the levels of genetic variation and differentiation between sites around the New Zealand coastline, including the Chatham Islands.  Significant differentiation was observed between the Chatham Islands and mainland New Zealand sample sites, indicating that these two regions form distinct populations. Interpretation of the results for the mainland sites was more complex. Mitochondrial sequence data detected no significant pairwise differentiation between mainland sites, although a pattern of isolation-by-distance was observed. However, evidence for genetic differentiation among mainland sites was weak based on the microsatellite DNA analysis. Although pairwise Gѕт levels were significant in some sites, this was not reflected in principal component analysis or Bayesian structure analysis. It is likely that through long range dispersal, migration is at or above the threshold for genetic connectivity, but below a level necessary for demographic connectivity. This is indicated by both the genetic structure reported here, along with previous studies showing limited dispersal of P. colias.</p>

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