Polymorphic Microsatellite DNA Markers Research Articles

Isolation and characterization of 17 polymorphic microsatellite loci with tri- and tetra-nucleotide repeat motifs for Ayu (Plecoglossus altivelis) using next-generation sequencing.

Ayu or sweetfish, Plecoglossus altivelis, an amphidromous fish ranging in the northwestern Pacific, is economically important inland fisheries and aquaculture resources. Genetic characterization of wild Ayu and derived culture seeds with competent molecular genetic markers is still insufficient for their sustainable use. Microsatellite DNA markers with larger repeat motifs (e.g. tri- and tetra-nucleotide motifs) are convenient and accurate compared with those having mono- and di-nucleotide motifs, but the latter motifs characterized most Ayu microsatellite markers developed previously. Here, we isolated and characterized 17 polymorphic microsatellite DNA markers with tri- and tetra-nucleotide repeat motif using next-generation sequencing. Alleles per locus varied from 6 to 23. The observed and expected heterozygosities ranged from 0.542 to1.000and 0.709to0.951, respectively. Polymorphic information content (PIC) of 15 out of the 17 loci were high (≧ 0.700), suggesting them to be highly informative. Twelve of the 17 loci were used for preliminary assignment test among three collections, and successfully allocated the examined fish to the original populations. The novel polymorphic microsatellite markers developed herein will be useful to examine the genetic diversity and population structure of wild Ayu and the effect of seed transplantation on native populations, providing a tool for conservation and sustainable adaptive management of this species.

Evaluating predator control using two non-invasive population metrics: a camera trap activity index and density estimation from scat genotyping

Context Invasive mammalian predators are a threat to biodiversity and agriculture globally, yet management outcomes for lethal predator control remain difficult to monitor and evaluate. Understanding whether changes in activity indices correspond to true changes in population density will help inform effective monitoring and management programs. Aims The aim of this study was to evaluate the effect of poison baiting on invasive red fox (Vulpes vulpes) populations using two alternative population metrics: fox activity from camera trap surveys and density estimation from scat genetic analysis. Methods We conducted before–after control–impact studies in two regions of semi-arid Australia (Wimmera and Mallee) by monitoring paired non-treatment and treatment sites during unbaited and baited periods. We estimated the effects of poison baiting on: (1) a monthly fox activity index, derived from an array of 10 off-road camera traps per site; and (2) fox density. To estimate density, we collected fox scats along 14-km transects, identified individuals using polymorphic microsatellite DNA markers and fitted spatially explicit capture–recapture models. Key results Fox activity remained consistently low at all sites except the Mallee non-treatment. The top-ranked models of fox activity and density contained an interaction between treatment and period, with an interactive and additive effect of region, respectively. However, there was little evidence that baiting reduced fox activity or density. In the unbaited period, fox densities ranged from 0.69 (95% CI: 0.47–1.0) to 1.06 (95% CI: 0.74–1.51) foxes km−2 and were similar across regions. Conclusions Camera traps have the potential to provide continuous index-based measures of fox populations but may not record sufficient observations to detect change. Indices can also be confounded by variations in animal behaviour. Scat genetic analysis is a viable option for providing direct estimates of population change at specific snapshots in time; however, this approach is considerably more expensive, and large sample sizes may be required if genotyping success is low. Implications Our study presents a rare example of multiple concurrent – and non-invasive – monitoring techniques to evaluate the effectiveness of predator control. We highlight the value of rigorous study designs and high-quality density information for designing predator management and monitoring programs.

Multiple mating by both sexes in an invasive insect species, Aethina tumida (Coleoptera: Nitidulidae).

Multiple mating by both sexes is common among sexually reproducing animals. Small hive beetles (SHB), Aethina tumida, are parasites of bee nests endemic to sub-Saharan Africa and have become a widespread invasive species. Despite the considerable economic damages they can cause, their basic biology remains poorly understood. Here we show that male and female small hive beetles can mate multiple times, suggesting that costs for mating are low in this species. In an invasive A. tumida population in the United States, a combination of laboratory experiments for males and paternity analysis with eight polymorphic DNA microsatellite markers for field-caught females were used to estimate the number of mating by both sexes. The data show that females and males can mate multiple times-females mated with up to eight males, whereas males mated with at least seven females. The results also showed that A.tumida displayed a skewed paternity, although this was not consistent among the tested females. Thus, first or last male advantage seem to be unlikely in A.tumida. Our observations that individuals of both sexes of A. tumida can mate multiple times opens new research avenues for examining drivers of multiple mating and determining the role it may play in promoting biological invasions.

Characterization of eight polymorphic microsatellite DNA markers and mitochondrial cytochrome c oxidase subunit II gene in Bali myna Leucopsar rothschildi

The aim of this study was to develop polymorphic DNA markers for Bali myna Leucopsar rothschildi. The mitochondrial cytochrome c oxidase subunit II (COII) gene was sequenced, and polymorphic microsatellite loci were searched using Next Generation Sequencing. Three haplotypes of mitochondrial COII gene were found in a Japanese population of Bali myna in human care. Eight polymorphic microsatellite DNA markers were also identified. In a sample group of 22 individuals, numbers of alleles and expected heterozygosities of the eight microsatellite loci ranged from two to three and 0·241 to 0·609, respectively. These results suggested that the genetic variation of this species might be low, similar to that of other threatened bird species.

Worker demography and behavior in a supercolonial ant colony: The case of the desert ant Cataglyphis niger

AbstractInsect societies headed by multiple queens (polygyny) raise evolutionary questions, such as how does genetic heterogeneity among colony members affect in‐nest interactions; or, are all queens equally reproductive or equally treated by workers? Answering such questions requires intensive and continuous observations of in‐nest behavior. Here, we addressed these questions in the polygyne supercolonial ant, Cataglyphis niger, using a barcoding system that enables the tracking of individual interactions, together with polymorphic DNA microsatellite markers that indicate the matriline and patriline of all individuals. Our findings that both queens and workers have low interrelatedness corroborate earlier reports regarding the supercolony structure of C. niger. Ovary inspection and worker genotyping revealed that all the queens contribute similarly to nest demography. Tracking positions of individual workers through time revealed that only a small proportion of them are constantly engaged in tending the queens and can be considered as retinue workers. However, genotyping these workers and the attended queens revealed no relationship to genetic relatedness, again typical of a true polygyne and supercolonial species. Unlike invasive supercolonial species, C. niger is native to Israel, enabling us to address questions regarding the driving forces, other than kin selection, that stabilize this society.

Genetic characterization of Benin's wild populations of Sarotherodon melanotheron melanotheron Rüppell, 1852.

The Cichlid fish Sarotherodon melanotheron is typically found in West and Central African estuaries and lagoons. It represents a good candidate for promoting tilapia farming in brackish waters. Understanding the genetic diversity in its populations from the hydrographical basins of Southern Benin is primordial before designing selective breeding programs. For this purpose, 202 samples collected from four rivers of Southern Benin and were genotyped using 15 polymorphic microsatellite DNA markers. Each river was split up into three sampling sites. We found significant global linkage disequilibrium across the genome of natural populations of this tilapia species overall the loci. However, when the loci that display aberrant Wright's (FIS and FST) were removed from the data, a linkage disequilibrium was detected for the remaining 11 loci and became compatible with the null hypothesis. Null alleles explained at least 20.58% of FIS variation. We found a significant isolation by distance across subsamples. Effective population size averaged 210 individuals, with a range from 36 to 517 individuals. Assuming that 79% of heterozygote deficits are explained by sib mating lead to a rough estimate of rsm = 0.4 of mating rate between full sibs within S. melanotheron subpopulations. The fish size correlated positively and significantly with the observed FIS (r = 0.58; p value = 0.04806). Reproduction system (endogamy) in S. melanotheron could explain the strong heterozygote deficit observed. Our results provide technical guidance for efficient management of this tilapia species' genetic resources for breeding programs in fresh and brackish waters.

Genetic Diversity in Cultured and Wild Population of Clarias gariepinus (Burchell, 1822) in Nigeria Using Random Amplified Polymorphic DNA (RAPD) and Microsatellite DNA

The population structure and genetic diversities of Clarias gariepinus from the cultured population at Chi Farm (Ajanla) and wild population at Asejire Reservoir (Asejire) were analysed using Random Amplified Polymorphic DNA (RAPD) and Microsatellite DNA markers. Using a CTAB protocol, genomic DNA was extracted from the caudal fins of 20 samples of live specimen collected from each population. Seven RAPD primers and seven pairs of microsatellite DNA primers were used to amplify different loci on the extracted genomic DNA by Polymerase Chain Reaction and the resultant DNA fragments were analysed on agarose gel. The RAPD primers amplified a total of 474 loci with 697 bands in all samples for the seven primers studied. The cultured population from Chi farm showed a total of 366 bands, while the wild population from Asejire Reservoir displayed 331 bands. The cultured population showed a negative inbreeding coefficient (F) of -0.173 ± 0.209, which statistically suggests excess heterozygosity, while a positive but low inbreeding coefficient of 0.042 ± 0.243 was estimated for the wild population. The Analysis of Molecular Variance (AMOVA) for both genetic markers indicated significant difference (p=0.01) between the two populations. The result of the study suggests a loss or on-going loss of genetic variability, which needs conservation intervention in the two populations studied.

Development and characterization of 13 polymorphic microsatellite DNA markers for pink salmon (Oncorhynchus gorbuscha) using next-generation sequencing approach

Journal of Applied IchthyologyVolume 33, Issue 6 p. 1204-1207 SHORT COMMUNICATION Development and characterization of 13 polymorphic microsatellite DNA markers for pink salmon (Oncorhynchus gorbuscha) using next-generation sequencing approach H. Tsukagoshi, Corresponding Author H. Tsukagoshi tsuk@iwate-u.ac.jp orcid.org/0000-0003-2601-805X Sanriku Fisheries Research Center, Iwate University, Kamaishi, Iwate, Japan Correspondence Hideharu Tsukagoshi, Sanriku Fisheries Research Center, Iwate University, Kamaishi, Japan. Email: tsuk@iwate-u.ac.jpSearch for more papers by this authorS. Terui, S. Terui Sanriku Fisheries Research Center, Iwate University, Kamaishi, Iwate, JapanSearch for more papers by this authorS. Sato, S. Sato Hokkaido National Fisheries Research Institute, Japan Fisheries Research and Education Agency, Sapporo, Hokkaido, JapanSearch for more papers by this authorS. Abe, S. Abe Sanriku Fisheries Research Center, Iwate University, Kamaishi, Iwate, JapanSearch for more papers by this author H. Tsukagoshi, Corresponding Author H. Tsukagoshi tsuk@iwate-u.ac.jp orcid.org/0000-0003-2601-805X Sanriku Fisheries Research Center, Iwate University, Kamaishi, Iwate, Japan Correspondence Hideharu Tsukagoshi, Sanriku Fisheries Research Center, Iwate University, Kamaishi, Japan. Email: tsuk@iwate-u.ac.jpSearch for more papers by this authorS. Terui, S. Terui Sanriku Fisheries Research Center, Iwate University, Kamaishi, Iwate, JapanSearch for more papers by this authorS. Sato, S. Sato Hokkaido National Fisheries Research Institute, Japan Fisheries Research and Education Agency, Sapporo, Hokkaido, JapanSearch for more papers by this authorS. Abe, S. Abe Sanriku Fisheries Research Center, Iwate University, Kamaishi, Iwate, JapanSearch for more papers by this author First published: 25 July 2017 https://doi.org/10.1111/jai.13436Citations: 2Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume33, Issue6December 2017Pages 1204-1207 RelatedInformation

Polymorphic DNA microsatellite markers for forensic individual identification and parentage analyses of seven threatened species of parrots (family Psittacidae).

The parrot family represents one of the bird group with the largest number of endangered species, as a result of habitat destruction and illegal trade. This illicit traffic involves the smuggling of eggs and animals, and the laundering through captive breeding facilities of wild-caught animals. Despite the huge potential of wildlife DNA forensics to determine with conclusive evidence illegal trade, current usage of DNA profiling approaches in parrots has been limited by the lack of suitable molecular markers specifically developed for the focal species and by low cross-species polymorphism. In this study, we isolated DNA microsatellite markers in seven parrot species threatened with extinction (Amazona brasiliensis, A. oratrix, A. pretrei, A. rhodocorytha, Anodorhynchus leari, Ara rubrogenys and Primolius couloni). From an enriched genomic library followed by 454 pyrosequencing, we characterized a total of 106 polymorphic microsatellite markers (mostly tetranucleotides) in the seven species and tested them across an average number of 19 individuals per species. The mean number of alleles per species and across loci varied from 6.4 to 8.3, with the mean observed heterozygosities ranging from 0.65 to 0.84. Identity and parentage exclusion probabilities were highly discriminatory. The high variability displayed by these microsatellite loci demonstrates their potential utility to perform individual genotyping and parentage analyses, in order to develop a DNA testing framework to determine illegal traffic in these threatened species.

Hierarchical Phylogeographic Structure of Coho Salmon in California

AbstractEvaluation of population genetic structure and variation is an important part of planning for the recovery and management of protected species. Data from 18 polymorphic microsatellite DNA markers were used to analyze the phylogeographic structure of protected Coho Salmon Oncorhynchus kisutch from populations throughout California. Fish from 30 locations in two evolutionarily significant units (ESUs) representing most of the extant populations in the state were studied. Multiple analyses indicated a hierarchical pattern of population structure: the greatest divergence was found at the broadest geographic scale (ESU), followed by the divergences between basins and populations within basins. The populations of the large Klamath River basin were consistently identified as a distinct phylogenetic group, nearly as divergent from all other populations as the two ESUs were from each other. All populations in different basins were differentiated from each other and a pattern of isolation by distance was found at a California‐wide scale, but not at smaller spatial scales. Similarly, most individuals were accurately assigned to their population of origin, and almost all misassignments were to an adjacent or geographically proximal basin, indicating that there is substantial gene flow within each region but much less between regions. The number of parents contributing to each population was highly variable and reflected larger patterns of genetic variation, which was found to be generally higher in the southerly, low‐elevation coastal populations than in the northern, interior, higher‐elevation populations. The results strongly support the current boundary between the two ESU regions, and the detailed understanding of phylogeographic structure provided here will help to guide the management and recovery of Coho Salmon at the southern end of their geographic range.Received August 25, 2015; accepted May 4, 2016 Published online August 12, 2016

Coping with potential bi-parental inbreeding: limited pollen and seed dispersal and large genets in the dioecious marine angiosperm Thalassia testudinum.

The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross‐fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling‐mating or bi‐parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back‐Reef and Mid‐Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by fine‐scale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3–1.6 m (max. 4.8 m) and of seeds was 0.3–0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m2 (range 3.4–11.4 m2) at Back‐Reef and 1.9 (range 1.87–1.92 m2) at Mid‐Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1–20.5 m2 at Back‐Reef and 0.1–16.9 m2 at Mid‐Lagoon. Maximal extensions of the genets, in 19 × 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back‐Reef and Mid‐Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (F IS) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back‐Reef). Contrary to our expectations, we did not find evidence of bi‐parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi‐parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back‐Reef and Mid‐Lagoon, respectively); such highly dispersed guerrilla‐like clonal growth form likely increases the probability of crossing between different potentially unrelated genets.

Genetic diversity and relatedness estimates for captive barramundi (Lates calcarifer, Bloch) broodstock informs efforts to form a base population for selective breeding

Aquaculture of barramundi or Asian seabass (Lates calcarifer) is growing in both Australia and Southeast Asia and there is substantial interest to improve production efficiency through selective breeding. The establishment of a large and genetically diverse base population is a prerequisite for a sustainable and long-term productive breeding program. Before selective breeding programs can begin for Australian barramundi it is important to assess the overall genetic diversity of current captive broodstock populations. To address this question, 407 captive barramundi broodstock from eight separate Australian broodstock populations were genotyped using 16 polymorphic microsatellite DNA markers. A Bayesian STRUCTURE analysis indicated that captive Australian broodstock are broadly divided into two genetic stocks. Multivariate analysis between broodstock individuals and pairwise FST between broodstock populations also supported the existence of two stocks. Comparisons with data obtained from natural stocks suggested that hatchery individuals were either sourced from the two stocks or represented an admixture between them. Genetic diversity was low within each broodstock population (allelic richness ranged from 2.67 to 3.42 and heterozygosity ranged from 0.453 to 0.537) and relatedness estimates within hatcheries were generally low (average r was equal to 0.141). We recommend sourcing captive individuals according to high levels of neutral genetic diversity and low levels of relatedness for the establishment of a base population. We also make recommendations about including genetically diverse wild individuals.

Isolation and characterization of polymorphic microsatellite markers in Bagarius yarrelli using RNA-Seq.

The yellow sisorid catfish (Bagarius yarrelli) is a vulnerable fish species. In this study, seven polymorphic microsatellite DNA markers for yellow sisorid catfish were described, using RNA-Seq methodology. In B. yarrelli (N = 44) from a Hekou wild population, allelic frequency, and observed and expected heterozygosities per locus varied from two to six, 0.0333 to 0.6793, and 0.0333 to 0.6004, respectively. One locus (Baya153) denoted notable separation from the Hardy-Weinberg equilibrium, after sequential Bonferroni correction (P < 0.05). The microsatellite markers described here will be useful for investigating population structure and genetic resource of B. yarrelli from different geographical locations.

Behavioural and genetic approaches to evaluate the effectiveness of deterrent marking by a parasitoid wasp

Some parasitoids deposit chemical signals after oviposition as an indication that the host has already been parasitized. This marking can deter subsequent conspecifics or one’s self from laying eggs in previously exploited hosts, thus reducing the risk of superparasitism. We investigated the egg laying behaviour of the parasitoid waspHyposoter horticola. In a laboratory experiment, we tested whether oviposition, post-oviposition marking, or both together deter subsequent oviposition by conspecifics. We then tested the effectiveness of the deterring mark under natural conditions using maternity assignment based on 14 polymorphic DNA microsatellite markers. The behavioural experiment showed that patch marking deters conspecifics from probing the host eggs, and oviposition deters those that probe from laying eggs in previously parasitized host clusters. These results were confirmed by the maternity assignment showing that under natural conditions, host egg clusters are primarily parasitized by a singleH. horticolafemale.

Development of twelve novel polymorphic microsatellite DNA markers for the Boeseman’s rainbowfish (Melanotaenia boesemani) and tests for their cross-utility in 21 rainbowfish species from West Papua (Indonesia)

We developed 12 microsatellite markers for the endangered Boeseman’s rainbowfish (Melanotaenia boesemani). Twenty-eight individuals from the type locality at Ayamaru Lake were examined, and all loci were polymorphic with a number of alleles per locus varying from 3 to 18. Average observed and expected heterozygosities were 0.681 and 0.678, respectively. Cross-species amplification was successfully obtained for 21 Melanotaenia species, with a number of alleles per locus ranging between 1 and 20. Average observed and expected heterozygosities varied between 0.105 and 0.708 and 0.118–0.755, respectively. Only 21 inbreeding coefficient (Fis) values presented a significant homozygote excess among the 264 locus-by-locus calculated values. Tests for genotyping errors revealed that four of these 21 significant Fis values could be explained by the presence of null alleles. These new microsatellite markers appear highly reliable for further conservation purposes or population genetic studies of the many rainbowfish endangered species.

Isolation and characterization of 16 highly polymorphic tetranucleotide microsatellite DNA markers in Paa spinosa

The giant spiny frog, Paa spinosa is a vulnerable species. By using a modified FIASCO (Fast Isolation by AFLP Sequences Containing repeats) method, we isolated and characterized 16 polymorphic tetranucleotide microsatellite loci for P. spinosa. These loci had high polymorphism when screened in 33 randomly caught individuals. The average number of alleles for 16 loci was 7.13 (range 2–14). Observed and expected heterozygosities were 0.152–0.818 and 0.144–0.918, respectively, and did not deviate from Hardy–Weinberg expectations. There was no evidence for scoring error due to stutter, null alleles, or large allele dropout. No significant association between pairs of loci was found after Bonferroni correction. These polymorphic loci will be effective for evaluating genetic diversity, population structure, gene flow and determining paternity in this frog, and also for conservation management.

Identification of twenty novel polymorphic microsatellite DNA markers from transcripts of the pearl oyster Pinctada fucata using next-generation sequencing approach

The pearl oyster, Pinctada fucata (Gould 1850) is a commercially important marine shellfish cultured for producing saltwater pearls mainly in China and Japan (Yu and Chu 2006). It is common in most areas of tropical and subtropical oceans and seas in the Pacific and Indian regions. In 1965, this specie was successfully propagated and reared under artificial conditions in Guangxi province in southern China and expanded rapidly to the neighbouring Guangdong and Hainan provinces subsequently (Meng et al. 1996). The pearls produced by the animals are referred to as ‘South China Sea Pearl’, accounting for over 90% production of the total marine pearls produced in China. For the last few years, some traits of P. fucata appear to have degenerated, due to overfishing, coastal water pollution and artificial propagation of years without recording their background, which hampered the advance of the pearl industry. Genetic improvement and culture of elite varieties should be carried out to prevent slowdown of the growth rate because of inbreeding depression and deterioration of the pearl quality. Microsatellite DNA markers have proved to be a useful tool for evaluating the level of genetic variation of natural populations in many fishery animals because of the high polymorphism, abundance, neutrality and codominance (Liu and Cordes 2004). Polymorphicmicrosatellite loci have been frequently applied in the analysis of genetic diversity of populations. In spite of some microsatellite loci in this species were reported (Tong et al. 2007; Kuang et al. 2009; Shi et al. 2009; Qu et al. 2010; You et al. 2012; Wu et al.

Incidence of a skeletal deformity (truncated upper jaw) in an isolated population of white-spotted charr Salvelinus leucomaenis

Although dorsal and caudal fin deformities (curvature), abnormal body color patterns, and fluctuating asymmetry of meristic characters have been previously reported for white-spotted charr (Salvelinus leucomaenis), the incidence of skeletally deformed individuals in the wild are extremely rare. Here, we report on skeletally deformed individuals of white-spotted charr with extremely truncated upper jaw, in a headwater reach of the Yoneshiro River, northern Honshu, Japan. In this study, we examined the genetic diversity of deformed and non-deformed populations of white-spotted charr using polymorphic microsatellite DNA markers. We also compared individual growth histories of deformed individuals with normal individuals using a back-calculation of fish lengths at previous ages from otolith annuli. We collected 41 and 100 individuals from the below- and above-waterfall sites, respectively. Of these, two individuals from the above-waterfall site were skeletally deformed, whereas the other individuals had a normal morphology. Microsatellite DNA genetic diversities of the above-waterfall population were notably lower than those of the just below-waterfall population. Individuals of the above-waterfall population had significantly higher internal relatedness and lower standardized heterozygosity values compared with those of the below-waterfall population, indicating higher inbreeding situation of the above-waterfall individuals compared with individuals in the below-waterfall site. Back-calculation of individual growth using otoliths revealed that deformed individuals grew significantly slower than sympatric normal individuals. Although incidence of deformed individuals in the wild might be related with accumulated inbreeding as suggested for other fishes, mechanisms for their long-term persistence in the wild remain unclear.

Development of 27 trinucleotide microsatellite markers for Saccharina japonica using next generation sequencing technology

Twenty-seven polymorphic trinucleotide microsatellite DNA markers were developed from Saccharina japonica, through paired-end Illumina sequencing data. Sixty-three gametophyte clones of the species, preserved indoor as germplasm resources were genotyped using these markers. The number of alleles ranged from 2 to 7 with an average 4.7 per locus. The gene diversity and expected heterozygosity varied from 0.171 to 0.774 and from 0.174 to 0.793, respectively. Sixteen loci could be successfully amplified in Saccharina longissima with 12 loci being polymorphic. These novel microsatellite DNA markers will be extremely useful in germplasm resource conservation and management of S. japonica and also in its related species S. longissima.

Isolation and characterization of polymorphic microsatellite DNA markers for an endangered freshwater fish in Korea, the bull-head torrent catfish Liobagrus obesus

The bull-head torrent catfish Liobagrus obesus (family Amblycipitidae) is an endangered freshwater fish in Korea. There has been a rapid decline in its population, caused by anthropogenic activities. This may also lead to reduced genetic diversity, which can significantly affect survival. Thus, molecular markers are important to assess the level of genetic variation. We developed 12 microsatellite markers that yielded an average of 7.83 alleles per locus. The average observed and expected heterozygosities were 0.663 and 0.699, respectively. This study is valuable for protecting the endangered species L. obesus; investigations of genetic diversity and population structure will provide useful information for conservation measures.