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1.
One-hundred and two unique loci were isolated from a microsatellite-enriched black-billed magpie Pica pica genomic library. Sixteen of these new loci, along with 148 existing microsatellite passerine loci, were tested for polymorphism in four unrelated black-billed magpies. We identified a total of 43 unique polymorphic loci (10 and 33 respectively) that we characterized in 24 unrelated individuals from a population in Guadix, Spain. The putative chromosomal locations of loci polymorphic in black-billed magpie were assigned based on the location of their orthologues in the assembled zebra finch and chicken genomes.  相似文献   

2.
Genetics of Vegetative Incompatibility in Cryphonectria parasitica   总被引:2,自引:0,他引:2       下载免费PDF全文
Vegetative incompatibility in the chestnut blight fungus, Cryphonectria parasitica, in Europe is controlled by six unlinked vic loci, each with two alleles. Four previously identified vic loci (vic1, vic2, vic3, and vic4) were polymorphic in European vegetative compatibility (vc) types. Two new loci, vic6 and vic7, also were identified among European vc types. In one cross, vic genes segregated independently at five loci, and 194 progeny were assigned to 32 vc types; none of these loci were linked. A total of 64 vc types were identified from all crosses. All 64 genotypes possible from six vic loci, each with two alleles (26 = 64), were identified and assigned to vc types. Based on our model, vc types v-c 5 and v-c 10, which had been used in previous genetic studies, differ by only five vic genes. Future studies of vc types in C. parasitica can use knowledge of vic genotypes for analysis of population genetic structure based on vic allele frequencies and to determine the effect of each vic gene on virus transmission between vc types.  相似文献   

3.
We have characterized 20 polymorphic microsatellite loci in the hihi Notiomystis cincta. Loci were identified by testing loci originally isolated in other avian species and by isolating new microsatellites from a hihi genomic library. These loci were characterized in unrelated hihi from a single population on Tiritiri Matangi Island (n = 98). Each locus displayed between two and 10 alleles, and observed heterozygosities ranged between 0.29 and 0.91. Nineteen of the 20 polymorphic loci could be assigned a chromosome location in the zebra finch, Taeniopygia guttata genome based on sequence homology.  相似文献   

4.
To test the hypothesis that the H-2 polymorphism is adaptive, the degree of polymorphism of loci linked to the H-2 complex on chromosome 17 of the house mouse was compared to the degree of polymorphism of loci located on other chromosomes. Published theoretical analyses show that polymorphisms subject to natural selection usually reduce the polymorphism of linked neutral loci. The first test of the hypothesis was based on data obtained from a survey of the polymorphism of 12 isozyme-encoding loci in wild house mice from Europe, North Africa and South America. Results of this test showed that, on the average, H-2-linked loci were as polymorphic as loci located on other chromosomes. In fact, the data suggested that H-2 linked loci might be more polymorphic than other loci. To test this hypothesis more rigorously, data for the 12 isozyme-encoding loci were augmented with data from published surveys of the polymorphisms of 59 loci in house mice from Europe and North America. Results of these tests showed that polymorphic loci linked to the H-2 complex tended to be more, rather than less, polymorphic than loci located on other chromosomes. The cluster of highly polymorphic loci seems to be related to linkage of these loci to the highly polymorphic H-2 complex, but the way in which the influence is exerted could not be readily explained.  相似文献   

5.
Tunisian hares (n = 45), currently assigned to Lepus capensis, were assayed for allelic variation at 40 allozyme loci, and allele frequencies at 32 loci were directly compared with earlier data of South African cape hares (L. capensis, n = 9) and European brown hares (L. europaeus, n = 244) to reveal genetic relationships among them. European mountain hares (L. timidus, n = 200) were used for outgroup comparison. In the Tunisian hares 27.5% of the loci were polymorphic with 2–4 alleles. Among all alleles at polymorphic loci, 15.1% occurred exclusively in Tunisian hares, 5.7% exclusively in cape hares, and 7.5% exclusively in brown hares at low frequencies. Not a single locus showed alternately fixed alleles between the samples of the L. capensis/L. europaeus complex. Levels of absolute and relative genetic differentiation among the samples of the L. capensis/ L. europaeus complex were low, relative to pairwise comparisons involving mountain hares. Diverse cluster analyses and multidimensional scaling of various pairwise genetic distance matrices concordantly grouped Tunisian hares with brown hares, and South African cape hares clustered only slightly farther apart, whereas mountain hares were distinctly separate. These results suggest regionally distinct phylogenetic units within an overall cohesive gene pool in the L. capensis/ L. europaeus complex, supporting Petter's view that all North African hares belong to L. capensis except for one local population of savanna hares, and that cape hares and brown hares are conspecific.  相似文献   

6.
Herbaceous peony, which belongs to sect. Paeonia, Paeonia L., Paeoniaceae, is not only a famous traditional flower in China; it is also highly regarded as an ornamental in Europe and the USA. On account of the abundance in germplasm resources and wide distribution ranges, herbaceous peony can be divided into three cultivar groups, the Chinese Peony Cultivar Group, the European Peony Cultivar Group and the Hybrid Peony Cultivar Group. However, most studies on genetic relationships in Paeonia are limited to the first group. This study used 15 polymorphic microsatellite markers that were developed by magnetic bead enrichment to explore the genetic diversity of 89 genotypes collected from Beijing, the USA and Canada and introduced to China. From 145 allelic loci that were detected from 15 primers, 140 (96.6%) were polymorphic. The number of allelic loci ranged from 4 to 16 with an average of 9.3, and the polymorphic index content ranged from 0.362 to 0.825 with an average of 0.678. Both cluster analysis and principal component analysis based on the 15 polymorphic primer pairs could distinguish the species from cultivars although the cluster analysis was better able to reflect the genetic relationships between all individuals. Some new insights about Paeonia L. are suggested. Furthermore, the 15 SSR markers have great significance as they will allow for furthering the studies on genetic diversity, genetic relationships and even the molecular marker-assisted breeding of Paeonia L.  相似文献   

7.
By combining biotin-enrichment protocol and next generation pyrosequencing, through 454 GS-FLX Titanium technology, 55 polymorphic microsatellites loci with perfect motif were isolated from the Rhone streber (Zingel asper), a critically endangered European fish species. Eight multiplex PCR kits were optimised in order to genotype a total of 58 polymorphic loci, including three previously published loci. The level of genetic diversity was assessed for 68 Z. asper, 30 Sander lucioperca, 33 Perca fluviatilis and four Gymnocephalus schraetzer individuals. Amplification success was also assessed on Romanichthys valsanicola and Zingel streber using single individuals. These markers will be useful to investigate the population structure of the highly fragmented Rhone streber. They represent a powerful tool for conservation issues and evolutionary approaches of this endemic species. Moreover, part of our markers demonstrated applicability to other percid species, allowing for potential applications to fisheries and aquaculture management.  相似文献   

8.
Genetic individualization based on non-invasive sampling is crucial for estimating the numbers of individuals in endangered mammalian populations. In sable (Martes zibellina)-poaching cases, identifying the number of animals involved is critical for determining the penalty. In addition, investigating animal numbers for wild sable populations requires genetic individualization when collecting several samples in neighboring regions. Microsatellites have been demonstrated to be reliable markers for individual identification. Thirty-three microsatellite loci derived from Mustelidae were selected to develop a genetic individualization method for sable. Three reference populations containing 54 unrelated sables were used to calculate allele number, allelic frequencies, and the polymorphic information content of each locus. The data were subsequently used to assess the validity of a combination of twelve loci for sable individualization. We defined twelve polymorphic loci that were easy to be amplified and genotyped. Four significant deviations from Hardy-Weinberg equilibrium were observed among the 12?loci in the three populations. The match probability of an individual from the reference populations with a random individual based on the 12?loci was 1.37?×?10?13. Using the combination of the twelve loci provides sufficient power to individualize sables considering the levels of microsatellite polymorphism observed. These loci were successfully applied to a case of sable poaching and provided valid evidence to determine the penalty. The genetic individualization of sable based on these loci might also be useful to investigate the numbers of animals in wild populations.  相似文献   

9.
Polymorphisms in human H chain V region genes from the VHIII gene family   总被引:8,自引:0,他引:8  
Polymorphisms of the Ig H chain V region (VH) genes were examined with probes from the coding and flanking regions of a gene from the largest VH gene family, VHIII. The 5'-flanking probe gave the simplest pattern and revealed the largest number of polymorphic fragments. Analysis of unrelated individuals and of families identified five polymorphic loci. Two alleles were detected for each of two of the loci, whereas a polymorphic band was scored as present or absent for the other three loci. The polymorphic fragments segregated in the expected Mendelian fashion and parental haplotypes could be assigned in all cases. Comparison of the patterns obtained with the flanking and coding region probes suggests that the human VHIII gene family is highly polymorphic and may contain several hundred V genes. This method, as well as the polymorphism detected, can be used to investigate the organization and germ-line variation of H chain V genes and their inheritance in normal individuals and in individuals with immunologic disorders.  相似文献   

10.
In the European bison, Bison bonasus (L), 15 proteins coded by 20 loci have been studied. Two of these loci (Es-3 and Ca) are polymorphic and the remaining 18 are monomorphic. The average heterozygosity of bisons in Polish herds is 3.5%. The value does not differ from those found in populations of other large mammals in spite of restoration of the European bison population from a mere 13 individuals.  相似文献   

11.
Mischocyttarus cassununga, a primitively eusocial Brazilian wasp, commonly found in urban environments, is an interesting model for studies on the evolution of social behaviour in hymenopteran insects. In this study, we constructed a microsatellite-enriched genomic library and presented primers for 18 microsatellite loci. For the analysis, 20 unrelated females were screened and all loci obtained were polymorphic. PCR amplification revealed from 3 (Mcas5b) to 17 (Mcas53b) alleles per locus ( $ \overline{x} = 8.3 $ ). We detected the levels of observed (H o) and expected (H e) heterozygosities ranging from 0.150 to 0.950 and 0.261 to 0.920, respectively. The polymorphic information content ranged from 0.238 to 0.915, averaging 0.680. All loci were in Hardy–Weinberg equilibrium and linkage disequilibrium was not detected after sequential Bonferroni correction (P?>?0.05). These molecular markers will allow further studies on sociogenetic structure, extensive population genetic analysis and diversity of M. cassununga and other Mischocyttarini species.  相似文献   

12.
In order to understand the population structure and genetic diversity among a set of 82 rice genotypes collected from different parts of the Asian countries including India were characterized using 39 microsatellite loci. The Population structure analysis suggested that the optimum number of subpopulations was four (K = 4) among the rice genotypes, whereas phylogenetic analysis grouped them into three populations. The results obtained from phylogenetic and STRUCTURE analysis proved to be very powerful for the differentiation of rice genotypes based on their place of origin. The genetic diversity analysis using 39 SSR loci yielded 183 scorable alleles, out of which 182 alleles were observed to be polymorphic with an average of 4.8 alleles per locus. The Polymorphism Information Content (PIC) values for all the polymorphic primers across 82 rice genotypes varied from 0.02 to 0.77, with an average of 0.50. Gene diversity (He) was found to be in the range of 0.02 (RM484) to 0.80 (OSR13) with an average value of 0.55, while heterozygosity (Ho) was observed with an average of 0.07, ranging from 0.01 (RM334) to 0.31 (RM316). The present study resulted in identification of seven highly polymorphic SSR loci viz., OSR13, RM152, RM144, RM536, RM489, RM259 and RM271 based on the parameters like PIC value (≥0.70), gene diversity (≥0.71), and polymorphic alleles (≥6). These seven polymorphic primers can effectively be used in further molecular breeding programs and QTL mapping studies of rice since they exhibited very high polymorphism over other loci. SSR analysis resulted in a more definitive separation of clustering of genotypes indicating a higher level of efficiency of SSR markers for the accurate determination of relationships between accessions.  相似文献   

13.
Malate dehydrogenase has been detected in four species of the super-species Jaera albifrons. Two polymorphic enzymatic systems occur showing a one banded pattern for homozygotes and a three banded pattern for heterozygotes. Two independant autosomal loci control the variation as is shown by intra- and interspecific crosses. In European populations of the three species studied, MDH-1 is polymorphic and MDH-2 is monomorphic. In the American species, J. posthirsuta, the locus MDH-2 is polymorphic and MDH-1 is monomorphic.  相似文献   

14.
Nine polymorphic microsatellite loci from the Madagascar paradise flycatcher Terpsiphone mutata were isolated using nonradioactive polymerase chain reaction (PCR)‐based techniques to screen an enriched genomic library. Seven polymorphic loci showed no evidence of null alleles and exhibited high levels of variation in 18 unrelated individuals (mean diversity = 0.80, mean number of alleles = 13.6). These loci are therefore suitable for analysis of population structure and paternity (exclusion probability for six unlinked loci = 0.9998).  相似文献   

15.
The wedge clam Donax trunculus is an Atlantic-Mediterranean warm-temperate species found from Senegal to the northern coast of France, including the Mediterranean and Black Sea. It is commercially exploited in several European countries and constitutes an important fishing resource due to its high economical value. To contribute to its conservation and management, nineteen microsatellite markers were isolated from two enriched genomic libraries. These loci were characterized in 30 clams from a single population from northwest Spain. The number of alleles per locus ranged from 2 to 17 and observed and expected heterozygosity varied from zero to 0.714 and from 0.078 to 0.950, respectively. Linkage disequilibrium was not detected and nine loci were in agreement with Hardy–Weinberg equilibrium. Fifteen polymorphic markers were arranged into three multiplex PCR sets to reduce both time and cost of microsatellite genotyping. This is the first time that polymorphic microsatellite markers have been reported for D. trunculus. These new markers provide a valuable resource for future population genetics studies and management and culture of this species.  相似文献   

16.
The complete mitochondrial genome of the brown brocket deer Mazama gouazoubira and a set of polymorphic microsatellite markers were identified by 454-pyrosequencing. De novo genome assembly recovered 98% of the mitochondrial genome with a mean coverage of 9-fold. The mitogenome consisted of 16,356 base pairs that included 13 protein-coding genes, two ribosomal subunit genes, 22 transfer RNAs and the control region, as found in other deer. The genetic divergence between the mitogenome described here and a previously published report was ∼0.5%, with the control region and ND5 gene showing the highest intraspecific variation. Seven polymorphic loci were characterized using 15 unrelated individuals; there was moderate genetic variation across most loci (mean of 5.6 alleles/locus, mean expected heterozygosity = 0.70), with only one locus deviating significantly from Hardy-Weinberg equilibrium, probably because of null alleles. Marker independence was confirmed with tests for linkage disequilibrium. The genetic variation of the mitogenome and characterization of microsatellite markers will provide useful tools for assessing the phylogeography and population genetic patterns in M. gouazoubira, particularly in the context of habitat fragmentation in South America.  相似文献   

17.
Random amplified polymorphic DNAs (RAPDs) were used to construct linkage maps of the parent of a longleaf pine (Pinus palustris Mill.) slash pine (Pinus elliottii Englm.) F1 family. A total of 247 segregating loci [233 (1∶1), 14 (3∶1)] and 87 polymorphic (between parents), but non-segregating, loci were identified. The 233 loci segregating 1∶1 (testcross configuration) were used to construct parent-specific linkage maps, 132 for the longleaf-pine parent and 101 for the slash-pine parent. The resulting linkage maps consisted of 122 marker loci in 18 groups (three or more loci) and three pairs (1367.5 cM) for longleaf pine, and 91 marker loci in 13 groups and six pairs for slash pine (952.9 cM). Genome size estimates based on two-point linkage data ranged from 2348 to 2392 cM for longleaf pine, and from 2292 to 2372 cM for slash pine. Linkage of 3∶1 loci to testcross loci in each of the parental maps was used to infer further linkages within maps, as well as potentially homologous counterparts between maps. Three of the longleaf-pine linkage groups appear to be potentially homologous counterparts to four different slash-pine linkage groups. The number of heterozygous loci (previously testcross in parents) per F1 individual, ranged from 96 to 130. With the 87 polymorphic, but non-segregating, loci that should also be heterozygous in the F1 progeny, a maximum of 183–217 heterozygous loci could be available for mapping early height growth (EHG) loci and for applying genomic selection in backcross populations.  相似文献   

18.
The incidence of chronic kidney disease varies by ethnic group in the USA, with African Americans displaying a two-fold higher rate than European Americans. One of the two defining variables underlying staging of chronic kidney disease is the glomerular filtration rate. Meta-analysis in individuals of European ancestry has identified 23 genetic loci associated with the estimated glomerular filtration rate (eGFR). We conducted a follow-up study of these 23 genetic loci using a population-based sample of 1,018 unrelated admixed African Americans. We included in our follow-up study two variants in APOL1 associated with end-stage kidney disease discovered by admixture mapping in admixed African Americans. To address confounding due to admixture, we estimated local ancestry at each marker and global ancestry. We performed regression analysis stratified by local ancestry and combined the resulting regression estimates across ancestry strata using an inverse variance-weighted fixed effects model. We found that 11 of the 24 loci were significantly associated with eGFR in our sample. The effect size estimates were not significantly different between the subgroups of individuals with two copies of African ancestry vs. two copies of European ancestry for any of the 11 loci. In contrast, allele frequencies were significantly different at 10 of the 11 loci. Collectively, the 11 loci, including four secondary signals revealed by conditional analyses, explained 14.2% of the phenotypic variance in eGFR, in contrast to the 1.4% explained by the 24 loci in individuals of European ancestry. Our findings provide insight into the genetic basis of variation in renal function among admixed African Americans.  相似文献   

19.
Thrips hawaiiensis (Morgan, 1913) is an important insect pest of fruits and vegetables. At present, it is primarily distributed in tropical and subtropical area. For a better understanding of the genetic makeup and migration patterns of T. hawaiiensis throughout the world, we isolated 11 novel polymorphic microsatellite loci from an enriched genomic library based on a biotin/streptavidin capture protocol. Genetic parameters were estimated on 80 individual thrips from two natural populations. The results showed that all 11 loci were highly polymorphic; the number of alleles ranged from six to 37, and nine loci demonstrated polymorphic information content (PIC) > 0.5. The observed (H O) and expected (H E) heterozygosities ranged from 0.350 to 0.925 and 0.307 to 0.952, respectively. Furthermore, only four locus/population combinations significantly deviated from Hardy–Weinberg equilibrium (HWE). These microsatellite markers have potential utility in population structure and gene flow studies of this species.  相似文献   

20.
A study based on AFLP markers was conducted to characterise the present population genetic structure of Carpinus betulus in Europe and to formulate guidelines for the use of this species in plantations on a local scale in Flanders. High within-population diversity and little (but significant) genetic differentiation were detected at both Flemish and European scales. However, there was a pattern of isolation by distance only at the European scale. Within-population gene diversity, a new rarefaction-based measure of number of genotypes (band richness) and percentage of polymorphic loci are lower north of major mountain chains, suggesting that the mountain ranges formed a second bottleneck for the hornbeam during postglacial recolonisation. In Flanders, despite lower gene diversity, there were more polymorphic loci than in other European populations, a pattern that might have been caused by the mixing of material through planting, e.g. in hedges. In view of these findings, it is advised to create a single Flemish seed zone and to use preferentially reproductive material from this seed zone for new plantations in Flanders.  相似文献   

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