Six polymorphic microsatellite loci in the Japanese Spanish mackerel,Scomberomorus niphonius

Six polymorphic microsatellite loci were isolated for genetic structure studies of the Japanese Spanish mackerel, Scomberomorus niphonius, a severely exploited marine fish species. The number of observed alleles for each locus ranged from seven to 41, and the values of expected and observed heterozygosities were 0.546–0.946 and 0.602–1.000, respectively. These microsatellite markers should prove to be a useful tool for estimating the population genetic structure and genetic variability of Japanese Spanish mackerel.     

PERMANENT GENETIC RESOURCES: Isolation and characterization of nine microsatellite loci from the chub mackerel, Scomber japonicus (Perciformes, Scombridae)

The stock abundance of the chub mackerel Scomber japonicus - a very important species for fisheries, particularly in Japan - in the Pacific Ocean off Japan has remained at a low level. For studying the population genetics of the chub mackerel, we isolated nine polymorphic microsatellite loci (12-31 alleles/locus; expected heterozygosity, 0.762-0.983) from this species. Cross-species amplification indicated that eight of the nine microsatellite loci in the blue mackerel S. australasicus were polymorphic and functional.     

Twelve polymorphic microsatellite loci from a dinucleotide-enriched genomic library of Japanese Spanish mackerel (Scomberomorus niphonius)

In the study, 34 microsatellite loci were isolated from a dinucleotide-enriched genomic library of Japanese Spanish mackerel (Scomberomorus niphonius). And 12 microsatellite loci were found to be polymorphic between 3 and 8 alleles. The number of observed and expected heterozygosity per locus in 23 individuals ranged from 0.6087 to 1.0000 and 0.8908 to 0.9773, respectively. Two loci significantly deviated from Hardy–Weinberg equilibrium after Bonferroni correction analysis and there was no significant linkage disequilibrium found between pairs of loci. As a result, 12 microsatellite loci probably located on different chromosome pairs and these polymorphic microsatellite loci should provide sufficient level of genetic diversity to investigate the fine-scale population structure and evaluate the breeding strategy in S. niphonius. The authors Shi-Chao Xing and Gen-Bo Xu contributed equally.     

Polymorphic microsatellite loci for Japanese Spanish mackerel (Scomberomorus niphonius)

We isolated and characterized 21 polymorphic microsatellite loci in Japanese Spanish mackerel (Scomberomorus niphonius) using a (GT)(13)-enriched genomic library. Forty individuals were collected from Qingdao, China. We found 3 to 24 alleles per locus, with a mean of 8.8. The observed and expected heterozygosities ranged from 0.263 to 0.975 and from 0.385 to 0.946, with means of 0.655 and 0.685, respectively. Deviation from Hardy-Weinberg proportions was detected at three loci. Two loci showed evidence for null alleles. These microsatellite markers will be useful for population genetic analysis of Japanese Spanish mackerel.     

Differential population structuring of two closely related fish species, the mackerel (Scomber scombrus) and the chub mackerel (Scomber japonicus), in the Mediterranean Sea

Population genetic structures of the mackerel (Scomber scombrus) and chub mackerel (Scomber japonicus) were studied in the Mediterranean Sea. Fragments of 272 bp (S. scomber) and 387 bp (S. japonicus) of the 5'-end of the mitochondrial control region were sequenced from spawning individuals collected off the coasts of Greece, Italy, Spain, and Portugal. High levels of mitochondrial control region haplotypic diversity (> 0.98) were found for both Scomber species. Nucleotide diversity was higher in the mackerel (0.022) than in the chub mackerel (0.017). Global F(ST) values were also higher and significant in the mackerel (0.024, P < 0.0001) as opposed to the chub mackerel (0.003, P > 0.05). Molecular variance analyses showed differential genetic structuring for these two closely related species. There is extensive gene flow between Mediterranean Sea and Atlantic Ocean populations of chub mackerel, which are organized into a larger panmictic unit. In contrast, Mediterranean Sea populations of mackerel show some degree of genetic differentiation and are structured along an east-west axis. The analysed eastern Mediterranean Sea mackerel populations (Greece, Italy) are clearly separated from that of the western Mediterranean Sea (Barcelona), which forms a panmictic unit with eastern Atlantic Ocean populations. The genetic structures of both species showed asymmetric migration patterns and indicated population expansion.     

Population structure of Atlantic mackerel inferred from RAD‐seq‐derived SNP markers: effects of sequence clustering parameters and hierarchical SNP selection

Restriction‐site‐associated DNA sequencing (RAD‐seq) and related methods are revolutionizing the field of population genomics in nonmodel organisms as they allow generating an unprecedented number of single nucleotide polymorphisms (SNPs) even when no genomic information is available. Yet, RAD‐seq data analyses rely on assumptions on nature and number of nucleotide variants present in a single locus, the choice of which may lead to an under‐ or overestimated number of SNPs and/or to incorrectly called genotypes. Using the Atlantic mackerel (Scomber scombrus L.) and a close relative, the Atlantic chub mackerel (Scomber colias), as case study, here we explore the sensitivity of population structure inferences to two crucial aspects in RAD‐seq data analysis: the maximum number of mismatches allowed to merge reads into a locus and the relatedness of the individuals used for genotype calling and SNP selection. Our study resolves the population structure of the Atlantic mackerel, but, most importantly, provides insights into the effects of alternative RAD‐seq data analysis strategies on population structure inferences that are directly applicable to other species.     

Isolation and characterization of microsatellite loci for the jack mackerel (<Emphasis Type="Italic">Trachurus murphyi</Emphasis> Nichols, 1920)

Eight microsatellite loci were developed for the jack mackerel (Trachurus murphyi), a fish of significant commercial importance in the Southeast Pacific. Genetic variation at these loci was examined in 15 samples from the locality of Talcahuano (Chile). All eight were highly polymorphic, with a number of alleles per locus ranging from 4 to 22 and an observed heterozygosity from 0.429 to 1. These markers will be useful to address issues of population genetics, ecology, conservation and fisheries management related to that species.     

Eleven new microsatellite markers in jack mackerel (Trachurus japonicus) derived from an enriched genomic library

Jack mackerel (Trachurus japonicus, Carangidae) are a commercially important fisheries resource in Korea. To understand patterns of genetic variation for conservation and management efforts, we developed microsatellite DNA markers fromT. japonicus. We report the isolation and characterization of eleven microsatellite loci isolated using an enrichment method based on magnetic/biotin capture of microsatellite sequences from a size-selected genomic library. To characterize each locus, 50 individuals from a naturalT. japonicus population in southern Korea were genotyped. All loci except one, KTJ38, were polymorphic with an average of 14 alleles per locus (range 6–23). The mean observed and expected heterozygosities were 0.70 (range 0.46–0.92) and 0.81 (range 0.49–1.00), respectively. Significant deviation from Hardy-Weinberg equilibrium was observed at three loci, KTj3, KTJ20 and KTJ28. Such high variability indicates that these microsatellites are useful markers for high-resolution analysis for population gemetic studies.     

Isolation and characterization of 19 novel microsatellite loci in Rhododendron aureum and Rhododendron brachycarpum (Ericaceae)

Nineteen polymorphic microsatellite loci are described for Rhododendron aureum Georgi (Ericaceae), an endangered species in Korea, and the closely related Rhododendron brachycarpum. The sequences containing repeat motifs were identified using low-depth next generation sequencing and 148 microsatellite loci were examined for amplification success and the detection of polymorphisms. All 19 loci were polymorphic and the number of alleles for these markers varied from 4 to 25, with an average of 15 alleles per locus. Three R. aureum loci showed departure from Hardy–Weinberg equilibrium (HWE) and one R. brachycarpum locus deviated significantly from HWE. These microsatellite loci will be useful for investigating the genetic diversity and population structure of both species.     

Isolation and characterization of 12 polymorphic microsatellite markers for the frog Pelophylax hubeiensis

Twelve polymorphic microsatellite loci were isolated from an (AC)n- and (AG)n-enriched DNA library for the endemic Chinese frog Pelophylax hubeiensis (Ranidae). The number of alleles per locus ranged from two to eight, with a mean of 5.17. The observed and expected heterozygosities ranged from 0.226 to 0.839 and from 0.204 to 0.826, with means of 0.568 and 0.656, respectively. No significant linkage disequilibrium was detected among these loci. However, two significant deviations from HWE were discovered at loci Pehu-11 and Pehu-12 (P<0.05). MICRO-CHECKER tests showed that null alleles could be present at locus Pehu-12. These polymorphic microsatellite loci can be employed for exploring mating mechanisms, population genetic structure and other relevant genetic investigations of P. hubeiensis.     

Isolation and characterization of microsatellite loci in the whale shark (Rhincodon typus)

In preparation for a study on population structure of the whale shark (Rhincodon typus), nine species-specific polymorphic microsatellite DNA markers were developed. An initial screening of 50 individuals from Holbox Island, Mexico found all nine loci to be polymorphic, with two to 17 alleles observed per locus. Observed and expected heterozygosity per locus ranged from 0.200 to 0.826 and from 0.213 to 0.857, respectively. Neither statistically significant deviations from Hardy-Weinberg expectations nor statistically significant linkage disequilibrium between loci were observed. These microsatellite loci appear suitable for examining population structure, kinship assessment and other applications.     

Isolation and characterization of microsatellite loci in Babylonia areolata and cross-species amplification in Babylonia formosae habei

Nine novel microsatellite primer pairs were presented for Babylonia areolata, representing the first microsatellite markers available for this genus. Levels of polymorphism were variable with 2 to 11 alleles per locus and expected heterozygosities ranging from 0.073 to 0.907 in 27 individuals of the population from which the loci were isolated. We found significant heterozygote deficit at one locus that might be attributable to null alleles. We were successful at cross-amplifying six loci in the congeneric B. formosae habei. These markers are therefore potentially useful for conservation studies, population structure assessment, ecological analyses and linkage map construction.     

Development and characterization of 11 microsatellite markers in the rock sparrow,Petronia petronia

Eleven polymorphic microsatellite loci were isolated in the passeriform Petronia petronia using the enrichment protocol FIASCO (fast isolation by AFLP of sequences containing repeats). We detected three to 13 alleles per locus in 25 specimens collected from an Italian population. The level of expected heterozygosity ranged from 0.439 to 0.856. One locus is sex linked to the Z chromosome. The total exclusionary probabilities using these loci for the first and the second parent were 0.978 and 0.999, respectively. These are the first microsatellite loci characterized from the rock sparrow that can be used for estimating population structure and for large‐scale parentage analysis.     

PERMANENT GENETIC RESOURCES: Ten polymorphic microsatellite markers for the pygmy rabbit (Brachylagus idahoensis)

We developed 10 polymorphic microsatellite loci for the pygmy rabbit (Brachylagus idahoensis). Nine of the 10 loci amplified reliably and had a low frequency of null alleles. Number of alleles per locus ranged from four to 12, and observed and expected heterozygosities ranged from 0.26 to 0.89 and from 0.63 to 0.88, respectively. These loci will be useful in determining population genetic structure and assessing patterns of gene flow in the pygmy rabbit.     

Isolation and characterization of twenty-one polymorphic microsatellite loci in the Tibetan macaque (<Emphasis Type="Italic">Macaca thibetana</Emphasis>)

Twenty-one microsatellite loci were isolated from AC-enriched library of Tibetan macaque (Macaca thibetana). The number of alleles at the 21 microsatellite loci ranged from 8 to 15, with an average of 12.2 per locus. Polymorphism information content (PIC) ranged from 0.805 to 0.910 with an average of 0.873. The observed and expected heterozygosities ranged from 0.208 to 0.792 and from 0.843 to 0.938, respectively. These microsatellite loci will be useful for future studies that relate to the genetic diversity and population structure of Tibetan macaque.     

Isolation and characterization of twenty-one polymorphic microsatellite loci in the Tibetan macaque (Macaca thibetana)

Twenty-one microsatellite loci were isolated from AC-enriched library of Tibetan macaque (Macaca thibetana). The number of alleles at the 21 microsatellite loci ranged from 8 to 15, with an average of 12.2 per locus. Polymorphism information content (PIC) ranged from 0.805 to 0.910 with an average of 0.873. The observed and expected heterozygosities ranged from 0.208 to 0.792 and from 0.843 to 0.938, respectively. These microsatellite loci will be useful for future studies that relate to the genetic diversity and population structure of Tibetan macaque.     

Microsatellite DNA markers in Populus tremuloides.

Markers for eight new microsatellite DNA or simple sequence repeat (SSR) loci were developed and characterized in trembling aspen (Populus tremuloides) from a partial genomic library. Informativeness of these microsatellite DNA markers was examined by determining polymorphisms in 38 P. tremuloides individuals. Inheritance of selected markers was tested in progenies of controlled crosses. Six characterized SSR loci were of dinucleotide repeats (two perfect and four imperfect), and one each of trinucleotide and tetranucleotide repeats. The monomorphic SSR locus (PTR15) was of a compound imperfect dinucleotide repeat. The primers of one highly polymorphic SSR locus (PTR7) amplified two loci, and alleles could not be assigned to a specific locus. At the other six polymorphic loci, 25 alleles were detected in 38 P. tremuloides individuals; the number of alleles ranged from 2 to 7, with an average of 4.2 alleles per locus, and the observed heterozygosity ranged from 0.05 to 0.61, with an average of 0.36 per locus. The two perfect dinucleotide and one trinucleotide microsatellite DNA loci were the most informative. Microsatellite DNA variants of four SSR loci characterized previously followed a single-locus Mendelian inheritance pattern, whereas those of PTR7 from the present study showed a two-locus Mendelian inheritance pattern in controlled crosses. The microsatellite DNA markers developed and reported here could be used for assisting various genetic, breeding, biotechnology, genome mapping, conservation, and sustainable forest management programs in poplars.     

Microsatellite primers in the Chinese dove tree, Davidia involucrata (Cornaceae), a relic species of the Tertiary

? Premise of the study: The first microsatellite primers were developed for Davidia involucrata, an endangered relic species of the Tertiary in China, to further describe its genetic variability and population structure. ? Methods and Results: Using the Fast Isolation by AFLP of Sequences Containing Repeats (FIASCO) protocol, 15 polymorphic microsatellite loci were isolated and characterized in 20 individuals from the germplasm collections of D. involucrata at the Hunan Forest Botanical Garden. High levels of polymorphism were revealed, with the total number of alleles per locus and the number of alleles per locus per individual ranging from two to 13 and from one to six, respectively. ? Conclusions: The multibanded patterns of microsatellite loci obtained in the current study confirmed that D. involucrata might be a polyploid species. The primers will be useful for studies of genetic diversity and for guiding conservation strategies for D. involucrata.     

Development of polymorphic microsatellite markers from barfin flounder (Verasper moseri) and their cross-species amplification

Barfin flounder (Verasper moseri) is a rare fish species in the world. Here, we reported 10 polymorphic microsatellite loci isolated from a dinucleotide-enriched genomic library of barfin flounder (Verasper moseri). The number of alleles, observed, and expected heterozygosity per locus in a test population ranged from 2 to 6, from 0.3333 to 1.0000, and from 0.4866 to 0.7774, respectively. One locus significantly deviated from Hardy–Weinberg equilibrium after Bonferroni correction and no significant linkage disequilibrium was found between pairs of loci. Cross-species amplification of these microsatellite loci in additional five fish species was performed. These polymorphic microsatellite loci would be useful for investigating genetic population structure and construction of genetic linkage map in Verasper moseri. Gui-Dong Miao and Chang-Wei Shao Contributed equally to this work.     

茶花鸡群体遗传多样性

茶花鸡是我国具有独特遗传特性的地方家禽品种,为了进一步阐明其群体遗传变异和遗传结构状况,采用了33个家鸡特异性的微卫星标记对该鸡种自然群体中30个个体进行了多态性电泳检测。33个微卫星座位共检测到105个等位基因,所有座位都呈现出多态性,每个座位的等位基因数在2~5个之间,平均每个座位等位基因数3.20个。群体平均杂合度和平均多态信息含量分别为0.612 9和0.527 6。结果表明,茶花鸡自然群体遗传多样性较丰富。