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1.
Microsatellite loci were isolated in Crassostrea corteziensis using (GT)n, (CT)n and (CTGT)n‐enriched genomic libraries. Within each of 45 sequenced clones, an average of three microsatellite regions (156 total) were observed. Thirty‐three primers were designed, from which 11 microsatellite loci amplified. Ten of those were polymorphic, with a range of two to 30 alleles. Three loci were not in Hardy–Weinberg equilibrium, and linkage disequilibrium was found for six pairs of loci. These microsatellite loci will be further tested for segregation distortions and null alleles to establish a set for population genetic studies of the species in the Northwest coasts of Mexico, and for optimization of aquaculture development. Seven of the microsatellite loci cross‐amplified in Crassostrea palmula, a sympatric species, and will be useful in further genetic studies.  相似文献   

2.
Polymorphic microsatellite loci were developed for Western Hemlock [Tsuga heterophylla (Raf.) Sarg], a prominent forest tree species in Western North America. Microsatellite‐enriched libraries were screened for (CA)n dinucleotide repeats from which 33 positive clones were sequenced. Polymerase chain reaction (PCR) primers for 16 microsatellite loci were prepared and tested against DNA from unrelated Western Hemlock trees. The 12 most informative microsatellite loci are reported here. From four to 22 alleles per locus were observed, with an average expected heterozygousity of 0.799.  相似文献   

3.
Twenty‐six polymorphic microsatellite markers were isolated from (AC)n and (AG)n microsatellite‐enhanced genomic libraries of the gray, short‐tailed opossum Monodelphis domestica. All 26 loci showed high allelic diversity, with allele numbers ranging from five to 11 in a subset of 35 animals. Normal Mendelian inheritance was confirmed for 24 loci by analysing allelic segregation in 10, two‐generation, families. Non‐amplifying (null) alleles were detected at two loci, which we recommend be used only if pedigree data are available. We conclude that all of these microsatellite markers would be useful for quantitative trait locus mapping and population genetic studies.  相似文献   

4.
We report the isolation of 23 microsatellite loci obtained from a (GA)n‐enriched genomic library of Oenocarpus bataua var. bataua. The average number of alleles per locus, the mean observed and expected heterozygosities for these microsatellite loci revealed a high level of variability. The transferability of the developed markers to other Oenocarpus species and other genera within the Euterpeae tribe was high, except for the Hyospathe genus.  相似文献   

5.
We identified 11 informative microsatellite loci in Tetratheca ericifolia from an (AG)n‐enriched library. Using these loci on 32 individuals from two populations (16 individuals from each), we detected an average of 11.3 alleles per locus (range of five to 21, average expected heterozygosity of 0.728), of which 56% were unique to one population or the other. All loci were amplifiable in seven to 12 of a further 12 species of Tetratheca under the same reaction conditions. The markers will be useful tools for evolutionary studies of this Australian endemic group.  相似文献   

6.
Twenty‐six microsatellite loci were isolated and characterized from the mangrove species Rhizophora mangle using (GT)n and (CT)n repeats. Eighty‐four per cent of the clones contained microsatellite sequences; the most common dinucleotides were the (GA/CT) and (CA/GT) repeats. Ten primers were selected to investigate the polymorphism among individuals of R. mangle from two natural populations of the Colombian Pacific Coast. The observed heterozygosity per locus varied from 0.20 to 0.80, the power of discrimination was 0.32–0.84 and the power of exclusion was 0.03–0.75. This set of microsatellites offers an efficient tool for population genetics studies on this species.  相似文献   

7.
Six microsatellite loci were isolated and characterized from genomic libraries enriched for (CA)n (GA)n (ATG)n, and (CAG)n, microsatellite motifs from Russula brevipes, a common ectomycorrhizal fungus that forms mutualisms with several species of trees in North America. The polymerase chain reaction primers were tested on 27 sporocarps of R. brevipes sampled in Douglas fir (Pseudotsuga menziesii), grey pine (Pinus sabiniana), and Sitka spruce (Picea sitchensis) stands. The number of alleles per locus ranged from two to 14 with expected heterozygosity values from 0.00 to 0.92 within populations. These are the first six microsatellite loci characterized from Russula brevipes that can be used for estimating genotypic diversity and population structure.  相似文献   

8.
Wilsonia backhousei is a clonal saltmarsh plant restricted to the southern latitudes of Australasia and threatened in New South Wales. We have identified eight informative microsatellite loci in the species from (AG)n‐ and (AC)n‐enriched libraries. In 48 samples from two populations we detected an average of five alleles per locus (range 2–8, average HE = 0.45), of which 72% were unique to one population or the other. Six of the eight loci were also amplifiable in Wilsonia rotundifolia under the same reaction conditions. The markers will be excellent tools for use in the management and conservation of both species.  相似文献   

9.
We developed eight PCR?primer pairs of polymorphic microsatellite loci for the túngara frog Physalaemus pustulosus. Genomic libraries were enriched for one of four microsatellite repeat sequences (CAn, GAn, ATGn and TAGAn). Following characterization of microsatellite loci by sequencing, primers were designed and PCR conditions optimized. Microsatellite PCR‐amplification was tested in 37 frogs from 8 populations in Costa Rica and Panama. Primer sequences, PCR conditions, allelelic diversities and observed as well as expected heterozygosities in the screened populations are described.  相似文献   

10.
Fifteen polymorphic microsatellite loci were developed for the Chinese soft‐shelled turtle (Pelodiscus sinensis) from the (GT)n microsatellite‐enriched genomic library, using the fast isolation by amplified fragment length polymorphism of sequences containing repeats protocol. The polymorphism of all 15 loci ranged from two to seven alleles with observed heterozygosities ranging from 0.03 to 0.98 (mean 0.43) in one population of 40 individuals. These novel loci will be helpful for understanding the population structure at genetic level and marker‐assisted breeding of this vulnerable species.  相似文献   

11.
Two microsatellite‐enriched libraries [(CAGA)n, (TAGA)n] were constructed using pooled DNA from three cyprinid species native to the Sacramento–San Joaquin Delta of California: Sacramento splittail (Pogonichthys macrolepidotus); Sacramento pikeminnow (Ptychocheilus grandis); and tui chub (Siphateles bicolor). Primers were designed for 105 loci and tested for levels of polymorphism in five cyprinid species found in the Delta: Sacramento splittail, Sacramento pikeminnow, tui chub, hitch (Lavinia exilicauda), and Sacramento blackfish (Orthodon microlepidotus). Fifty‐one loci were polymorphic for at least one species and 31 loci were polymorphic for multiple species. The number of polymorphic loci per species ranged from 16 to 26.  相似文献   

12.
Correlations between heterozygosity and fitness are frequently found but rarely well understood. Fitness can be affected by single loci of large effect which correlate with neutral markers via linkage disequilibrium, or as a result of variation in genome‐wide heterozygosity following inbreeding. We explored these alternatives in the common buzzard, a raptor species in which three colour morphs differ in their lifetime reproductive success. Using 18 polymorphic microsatellite loci, we evaluated potential genetic differences among the morphs which may lead to subpopulation structuring and tested for correlations between three fitness‐related traits and heterozygosity, both genome wide and at each locus separately. Despite their assortative mating pattern, the buzzard morphs were found to be genetically undifferentiated. Multilocus heterozygosity was only found to be correlated with a single fitness‐related trait, infection with the blood parasite, Leucocytozoon buteonis, and this was via interactions with vole abundance and age. One locus also showed a significant relationship with blood parasite infection and ectoparasite infestation. The vicinity of this locus contains two genes, one of which is potentially implicated in the immune system of birds. We conclude that genome‐wide heterozygosity is unlikely to be a major determinant of parasite burden and body condition in the polymorphic common buzzard.  相似文献   

13.
A genomic cosmid library was used to develop seven highly polymorphic microsatellite markers for the Mexican spotted owl (Strix occidentalis lucida). These are the first reported microsatellite markers derived from this species. The cloned and sequenced repeat motifs include a triplet repeat of (AAT)n, two tetranucleotide repeats of (GATA)n, a tetranucleotide repeat of (ATCC)n, a compound repeat of (GA)n(GATA)n and the two pentanucleotide repeats (AGAAT)n and (ATTTT)n. The microsatellites described represent six presumably independent loci with the two pentanucleotide repeats having originated from a single cosmid. Primer pairs allow locus‐specific amplification of each marker from Mexican spotted owl genomic DNA.  相似文献   

14.
The low levels of allozymic variability found in the Critically Endangered Borderea chouardii prompted us to develop microsatellite markers to assess the genetic variability and population structure for the adequate conservation management of this species. A (CTT)n‐enriched partial genomic library was constructed. Ten polymorphic microsatellite loci were isolated from it, rendering 51 alleles in 47 individuals analysed. The allelic pattern observed for all of the loci with more than two alleles suggests that B. chouardii is tetraploid.  相似文献   

15.
Microsatellite loci were isolated in Haliotis fulgens using a (CT)n enriched‐genomic library. From 33 sequenced clones, 21 microsatellites regions were identified, 15 with the expected (CT)n. Eight microsatellite loci were amplified, six of which were polymorphic with a range of three to 20 alleles, and five cross‐amplified in two other species (Haliotis rufescens and Haliotis corrugata). These microsatellites will be useful as population genetic markers in the three species.  相似文献   

16.
We report the isolation and characterization of 11 polymorphic tetranucleotide microsatellite loci in the common genet (Genetta genetta) from genomic libraries enriched for (AAAG) n and (AGAT) n repeat sequences. We chose to develop tetranucleotide repeats because they can be scored less ambiguously. In a sample of 25 individuals, we observed between four and thirteen alleles per locus and their observed and expected heterozygosities ranged from 0.60 to 0.84 and from 0.68 to 0.92, respectively. All genotypic frequencies conformed to Hardy–Weinberg equilibrium expectations and there were no instances of linkage disequilibrium detected between pairs of loci. These loci will be of use in studies of population genetics, historical demography, and molecular ecology of the common genet.  相似文献   

17.
Abundance, polymorphism and genetic mapping of microsatellites in rice   总被引:71,自引:0,他引:71  
Dinucleotide microsatellites have been characterized and used as genetic markers in rice. Screening of a rice genomic library with poly(dG-dA)·(dC-dT) and poly(dG-dT)·(dC-dA) probes indicated that (GA)n repeats occurred, on average, once every 225 kb and (GT)n repeats once every 480 kb. DNA sequencing of ten randomly selected microsatellites indicated that the numbers of repeats ranged from 12 to 34 and that the patterns of microsatellites in rice were similar to those of humans and other mammals. Primers to these microsatellite loci as well as to four published microsatellite-containing sequences have been designed and degrees of polymorphism has been examined with 20 rice accessions. Multiple alleles, ranging from 5 to 11, have been observed at all the microsatellite loci in 20 rice accessions. Alleles specific to two cultivated subspecies, indica and japonica, were found in some microsatellite loci. Heterozygosity values of all the microsatellite markers were significantly higher than those of RFLP markers, based upon a parallel comparison. Ten microsatellite loci have been genetically mapped to four rice chromosomes. The genomic distribution of microsatellites appears to be random in rice.  相似文献   

18.
Microsatellite loci were characterized for the monk parakeet (Myiopsitta monachus) from a GTn‐enriched genomic library. Twelve of 14 microsatellite loci were polymorphic, averaging 6.7 alleles per locus across the 20 individuals genotyped. Mean expected heterozygosity was 0.72, with locus‐specific values ranging from 0.53 to 0.90. An equally high multilocus probability of identity (2.48 × 10?12) was revealed for this set of loci. In addition, all 12 loci were demonstrated to cross‐amplify to varying extents within three additional parrot genera suggesting their potential utility for population‐level studies in a broad range of Neotropical psittacines.  相似文献   

19.
Primers were developed for 17 microsatellite loci from an enriched (GATA)n library from DNA from Gila bicolor obesa. These primers were tested for cross‐species amplification in Gila bicolor snyderi, Gila orcutti and Gila coerulea.  相似文献   

20.
The sandfly Lutzomyia longipalpis, an important vector of visceral leishmaniasis in the New World, is believed to be a species complex. In an effort to better understand population dynamics and speciation in this vector we developed a panel of dinucleotide — (CA)n— microsatellite loci using an enrichment technique. Eleven polymorphic loci that produced consistent allelic banding patterns were characterized using a laboratory population of L. longipalpis. These dinucleotide microsatellite loci were more polymorphic than trinucleotide microsatellites characterized in wild‐caught samples of two other sandfly species; the variability of these loci was unexpected because the laboratory flies were believed to be inbred.  相似文献   

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