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394 results for “Microsatellite data”
Data from: Varver: a database of microsatellite variation in vertebrates
Understanding how genetic variation is maintained within a species is important in ecology, evolution, conservation and population genetics. Tremendous efforts have been made to evaluate the patterns of genetic variation in natural populations of various species. For this purpose, microsatellites have played a major role since the 1990s. Here we describe a comprehensive database, varver (Variation in Vertebrates) that provides complete information regarding microsatellite variation in natural populations of vertebrates. For each species, varver includes basic information of the species, a list of publications reporting the microsatellite variation, and tables of genetic variation within and between populations (heterozygosity and FST). The geographic location and rough sampling range are also shown for each sampled population. The database should be useful for researchers interested in not only specific species but also comparing multiple species. We discuss the utility of microsatellite data, particularly for meta-analyses that involve multiple microsatellite loci from various species. We show that in such analyses, it is extremely important to correct for biases caused by differences in mutation rate, mainly due to repeat unit and number. It is an important task to understand how genetic variation is maintained within a species in ecology, evolution, conservation and population genetics. A tremendous amount of effort has been made to evaluate the patterns of genetic variation in natural populations of various species. For this purpose, microsatellites have played the major role since 1990'. We here develop a comprehensive database that provide full information of microsatellite variations in natural populations of vertebrates, named VarVer. For each species, VarVer includes basic information of the species, a list of publications that reported microsatellite variation, and tables of genetic variation within and between populations (heterozygosity and Fst). The geographic location and rough sampling range are also shown for each sampled population. The database should be useful for not only researchers who are interested in specific species but also those who are interested in comparing multiple species. We discuss how useful microsatellite data are particularly for meteanalyses that involve a number of microsatellite loci from various species. In such analyses, we show that it is extremely important to correct for biases caused by the difference in the mutation rate, mainly due to the repeat unit and number.
Data from: Neither philopatric nor panmictic: microsatellite and mtDNA evidence suggests lack of natal homing but limits to dispersal in Pacific lamprey
Most species with lengthy migrations display some degree of natal homing; some (e.g., migratory birds and anadromous salmonids) show spectacular feats of homing. However, studies of the sea lamprey (Petromyzon marinus) indicate that this anadromous species locates spawning habitat based on pheromonal cues from larvae rather than through philopatry. Previous genetic studies in the anadromous Pacific lamprey (Entosphenus tridentatus) have both supported and rejected the hypothesis of natal homing. To resolve this, we used nine microsatellite loci to examine population structure in 965 Pacific lamprey from 20 locations from central British Columbia to southern California, and supplemented this analysis with mitochondrial DNA restriction fragment length polymorphism analysis on a subset of 530 lamprey. Microsatellite analysis revealed: 1) relatively low but often statistically significant genetic differentiation among locations (97% pairwise FST values were less than 0.04 but 73.7% were significant); and 2) weak but significant isolation-by-distance (r2 = 0.0565, P = 0.0450) but no geographic clustering of samples. The few moderate FST values involved comparisons with sites that were geographically distant or far upstream. The mtDNA analysis—although providing less resolution among sites (only 4.7% FST values were significant)—was broadly consistent with the microsatellite results: 1) the southernmost site and some sites tributary to the Salish Sea were genetically distinct; and 2) southern sites showed higher haplotype and private haplotype richness. These results are inconsistent with philopatry, suggesting that anadromous lampreys are unusual among species with long migrations, but suggest that limited dispersal at sea precludes panmixia in this species.
Data from: Microsatellite mutation rate in Atlantic sturgeon (Acipenser oxyrinchus)
Understanding mutation rates can greatly extend the utility of population and conservation genetic analyses. Herein we present an estimate of genome-wide microsatellite mutation rate in Atlantic sturgeon (Acipenser oxyrinchus) based on parent-offspring transmission patterns. We screened 307 individuals for parentage and mutation-rate analysis applying 43 variable markers. Out of 13,228 allele transfers, 11 mutations were detected, producing a mutation rate of 8.3x10-4 per locus per generation (95%CI: 1.48x10-3, 4.15x10-4). Single-step mutations predominated and there were trends toward mutations in loci with greater polymorphism and allele length. Two of the detected mutations were most probably cluster mutations, being identified in 12 and 28 sibs, respectively. Finally, we observed evidences of polyploidy based on the sporadic presence of 3 or 4 alleles per locus in the genotyped individuals, supporting previous reports of incomplete diploidization in Atlantic sturgeon.
Data from: Isolation and characterization of 145 polymorphic microsatellite loci for the common frog (Rana temporaria)
We describe primers and polymerase chain reaction conditions to amplify 145 di-, tri- and tetranucleotide microsatellite loci from the common frog (Rana temporaria), a species commonly used as a model in ecological and evolutionary research. Primers were tested on 46 individuals from two Fennoscandian populations and yielded an average of six to nine alleles per locus (range = 1–30) depending on the population. Average observed heterozygosities in the two populations were 0.16 (range = 0–0.91) and 0.36 (range = 0–1).
Data from: Transcriptome-wide mining, characterization, and development of microsatellite markers in Lychnis kiusiana (Caryophyllaceae)
Background: Lychnis kiusiana Makino is an endangered perennial herb native to wetland areas in Korea and Japan. Despite its conservational and evolutionary significance, population genetic resources are lacking for this species. Next-generation sequencing has been accepted as a rapid and cost-effective solution for the identification of microsatellite markers in nonmodel plants. Results: Using Illumina HiSeq 2000 sequencing technology, we assembled 67,498,600 reads into 91,900 contigs and identified 11,403 microsatellite repeat motifs in 9,563 contigs. A total of 4,510 microsatellite-containing transcripts had Gene Ontology (GO) annotations, and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified 124 pathways with significant scores. Many microsatellites in the L. kiusiana leaf transcriptome were linked to genes involved in the plant response to light intensity, salt stress, temperature stimulus, and nutrient and water deprivation. A total of 12,486 single-nucleotide polymorphisms (SNPs) were identified on transcripts harboring microsatellites. The analysis of nucleotide substitution rates for 2,389 unigenes indicated that 39 genes were under strong positive selection. The primers of 6,911 microsatellites were designed, and 40 of 50 selected primer pairs were consistently and successfully amplified from 51 individuals. Twenty-five of these were polymorphic, and the average number of alleles per SSR locus was 6.96, with a range from 2 to 15. The observed and expected heterozygosities ranged from 0.137 to 0.902 and 0.131 to 0.827, respectively, and locus-specific FIS estimates ranged from -0.116 to 0.290. Eleven of the 25 primer pairs were successfully amplified in three additional species of Lychnis: 56% in L. wilfordii, 64% in L. cognata and 80% in L. fulgens. Conclusions: The transcriptomic SSR markers of Lychnis kiusiana provide a valuable resource for understanding the population genetics, evolutionary history, and effective conservation management of this species. Furthermore, the identified microsatellite loci linked to the annotated genes should be useful for developing functional markers of L. kiusiana. The developed markers represent a potentially valuable source of transcriptomic SSR markers for population genetic analyses with moderate levels of cross-taxon portability.
Data from: Microsatellite analyses across three diverse vertebrate transcriptomes (Acipenser fulvescens, Ambystoma tigrinum, and Dipodomys spectabilis)
Historically, many population genetics studies have utilized microsatellite markers sampled at random from the genome and presumed to be selectively neutral. Recent studies, however, have shown that microsatellites can occur in transcribed regions, where they are more likely to be under selection. In this study, we mined microsatellites from transcriptomes generated by 454-pyrosequencing for three vertebrate species: lake sturgeon (Acipenser fulvescens), tiger salamander (Ambystoma tigrinum), and kangaroo rat (Dipodomys spectabilis). We evaluated (i) the occurrence of microsatellites across species; (ii) whether particular gene ontology terms were over-represented in genes that contained microsatellites; (iii) whether repeat motifs were located in untranslated regions or coding sequences of genes; and (iv) in silico polymorphism. Microsatellites were less common in tiger salamanders than in either lake sturgeon or kangaroo rats. Across libraries, trinucleotides were found more frequently than any other motif type, presumably because they do not cause frameshift mutations. By evaluating variation across reads assembled to a given contig, we were able to identify repeat motifs likely to be polymorphic. Our study represents one of the first comparative data sets on the distribution of vertebrate microsatellites within expressed genes. Our results reinforce the idea that microsatellites do not always occur in noncoding DNA, but commonly occur in expressed genes.
Data from: Development of conserved microsatellite markers of high cross-species utility in bat species (Vespertilionidae, Chiroptera, Mammalia)
Comparative ecological and behavioural studies of the widespread and diverse Vespertilionidae, which comprise almost 400 of the 1,100 bat species, have been limited by the availability of markers. The potential of new methods for developing conserved microsatellite markers which possess enhanced cross-species utility has recently been illustrated in studies of birds. We have applied these methods to develop enhanced microsatellite markers for vespertilionid bats, in particular for the genus Myotis (103 species). We compared published bat microsatellites with their homologs in the genome sequence of the little brown bat, Myotis lucifugus to create consensus sequences which were used to design candidate primer sets. Primer sets were then tested for amplification and polymorphism in 22 species of bat from nine of the largest families (including 11 Vespertilionidae). Of 46 loci tested, 33 were polymorphic, on average, for each of seven Myotis species tested, 20 in each of four non-Myotis vespertilionid species, and two in 11 non-vespertilionid species.
Data from: Characterization of 42 polymorphic microsatellite loci in Mimulus ringens (Phrymaceae) using Illumina sequencing
Premise of the study: Microsatellite markers were isolated and characterized in Mimulus ringens (Phrymaceae), a herbaceous wetland perennial, to facilitate studies of mating patterns and population genetic structure. Methods and Results: A total of 42 polymorphic loci were identified from a sample of 24 individuals from a single popula- tion in Ohio, USA. The number of alleles per locus ranged from two to nine, and median observed heterozygosity was 0.435. Conclusions: This large number of polymorphic loci will enable researchers to quantify male fitness, patterns of multiple pa- ternity, selfing, and biparental inbreeding in large natural populations of this species. These markers will also permit detailed study of fine-scale patterns of genetic structure.
Data from: Measuring population differentiation using GST or D? A simulation study with microsatellite DNA markers under a finite island model and nonequilibrium conditions
Genetic differentiation of populations is a key question in population genetic investigations. Wright's FST (and its relatives such as GST) has been a standard measure of differentiation. However, the deficiencies of these indexes and their significance have been increasing realized in recent years, leading to some new measures being proposed, such as Jost's (2008) D. This has also stimulated some considerable debate which, in certain sense, makes empirical biologists even more confused, for example, on statistics which should be used for estimating population differentiation. Here we report a simulation study with neutral microsatellite DNA loci under a finite island model to compare the performance of GST and D, under non-equilibrium conditions, in particular. Our results suggest that there exist fundamental differences between the two statistics and neither GST nor D operate satisfactorily in all situations for quantifying differentiation. D is very sensitive to mutation models but GST noticeably less so ...
Data from: Characterizing genic and non-genic molecular markers: comparison of microsatellites and SNPs
The implications of transitioning to single nucleotide polymorphism (SNPs) from microsatellite markers (MSs) have been investigated in a number of population genetics studies, but the effect of genomic location on the amount of information each type of marker reveals has not been explored in detail. We developed novel SNP markers flanking 1 kb regions of 13 genic (within gene or <1 kb away from gene) and 13 nongenic (>10 kb from annotated gene) MSs in the threespine stickleback genome to obtain comparable data for both types of markers. We analysed patterns of genetic diversity and divergence on various geographic scales after converting the SNP loci within each genomic region into haplotypes. Marker type (SNP haplotype or MS) and location (genic or nongenic) significantly affected most estimates of population diversity and divergence. Between-lineage divergence was significantly higher in SNP haplotypes (genic and nongenic), however, within-lineage divergence was similar between marker types. Most divergence and diversity measures were uncorrelated between markers, except for population differentiation which was correlated between MSs and SNP haplotypes (both genic and nongenic). Broad-scale population structure and assignment were similarly resolved by both marker types, however, only the MSs were able to delimit fine-scale population structuring, particularly when genic and nongenic markers were combined. These results demonstrate that estimates of genetic variability and differentiation among populations can be strongly influenced by marker type, their genomic location in relation to genes and by the interaction of these two factors. This highlights the importance of having an awareness of the inherent strengths and limitations associated with different molecular tools to select the most appropriate methods for accurately addressing various ecological and evolutionary questions.
Data from: Microsatellite analysis of genetic diversity and population structure of Arabian horse populations
The Arabian horse ignites imagination throughout the world. Populations of this breed exist in many countries, and recent genetic work has examined the diversity and ancestry of a few of these populations in isolation. Here we explore seven different populations of Arabians represented by 682 horses. Three of these are Middle Eastern populations from near the historical origin of the breed, including Syrian, Persian, and Saudi Arabian. The remaining Western populations are found in Europe (the Shagya-Arabian and Polish-Arabian) and America (American-Arabian). Analysis of genetic structure was carried out using 15 microsatellite loci. Genetic distances, AMOVA, factorial correspondence analysis and a Bayesian method were applied. The results consistently show higher level of diversity within the Middle Eastern populations than the Western populations. The Western Arabian populations were the main source of among populations variation. Genetic differentiation was not strong among all Middle Eastern populations, but all American-Arabians showed differentiation from Middle Eastern populations and were somewhat uniform among themselves. Here, we explore the diversities of many different populations of Arabian horses, and find that populations not from the Middle East have noticeably lower levels of diversity, which may adversely affect the health of these populations.
Data from: Mining microsatellite markers from public expressed sequence tags databases for the study of threatened plants
Background: Simple Sequence Repeats (SSRs) are widely used in population genetic studies but their classical development is costly and time-consuming. The ever-increasing available DNA datasets generated by high-throughput techniques offer an inexpensive alternative for SSRs discovery. Expressed Sequence Tags (ESTs) have been widely used as SSR source for plants of economic relevance but their application to non-model species is still modest. Methods: Here, we explored the use of publicly available ESTs (GenBank at the National Center for Biotechnology Information-NCBI) for SSRs development in non-model plants, focusing on genera listed by the International Union for the Conservation of Nature (IUCN). We also search two model genera with fully annotated genomes for EST-SSRs, Arabidopsis and Oryza, and used them as controls for genome distribution analyses. Overall, we downloaded 16 031 555 sequences for 258 plant genera which were mined for SSRsand their primers with the help of QDD1. Genome distribution analyses in Oryza and Arabidopsis were done by blasting the sequences with SSR against the Oryza sativa and Arabidopsis thaliana reference genomes implemented in the Basal Local Alignment Tool (BLAST) of the NCBI website. Finally, we performed an empirical test to determine the performance of our EST-SSRs in a few individuals from four species of two eudicot genera, Trifolium and Centaurea. Results: We explored a total of 14 498 726 EST sequences from the dbEST database (NCBI) in 257 plant genera from the IUCN Red List. We identify a very large number (17 102) of ready-to-test EST-SSRs in most plant genera (193) at no cost. Overall, dinucleotide and trinucleotide repeats were the prevalent types but the abundance of the various types of repeat differed between taxonomic groups. Control genomes revealed that trinucleotide repeats were mostly located in coding regions while dinucleotide repeats were largely associated with untranslated regions. Our results from the empirical test revealed considerable amplification success and transferability between congenerics. Conclusions: The present work represents the first large-scale study developing SSRs by utilizing publicly accessible EST databases in threatened plants. Here we provide a very large number of ready-to-test EST-SSR (17 102) for 193 genera. The cross-species transferability suggests that the number of possible target species would be large. Since trinucleotide repeats are abundant and mainly linked to exons they might be useful in evolutionary and conservation studies. Altogether, our study highly supports the use of EST databases as an extremely affordable and fast alternative for SSR developing in threatened plants.
Data from: 'True' null allele detection in microsatellite loci: a comparison of methods, assessment of difficulties, and survey of possible improvements
Null alleles are alleles that for various reasons fail to amplify in a PCR assay. The presence of null alleles in microsatellite data is known to bias the genetic parameter estimates. Thus, efficient detection of null alleles is crucial, but the methods available for indirect null allele detection return inconsistent results. Here, our aim was to compare different methods for null allele detection, to explain their respective performance and to provide improvements. We applied several approaches to identify the 'true' null alleles based on the predictions made by five different methods, used either individually or in combination. First, we introduced simulated 'true' null alleles into 240 population data sets and applied the methods to measure their success in detecting the simulated null alleles. The single best-performing method was ML-NullFreq_frequency. Furthermore, we applied different noise reduction approaches to improve the results. For instance, by combining the results of several methods, we obtained more reliable results than using a single one. Rule-based classification was applied to identify population properties linked to the false discovery rate. Rules obtained from the classifier described which population genetic estimates and loci characteristics were linked to the success of each method. We have shown that by simulating 'true' null alleles into a population data set, we may define a null allele frequency threshold, related to a desired true or false discovery rate. Moreover, using such simulated data sets, the expected null allele homozygote frequency may be estimated independently of the equilibrium state of the population.
Data from: Genome-wide gene-associated microsatellite markers for the model invasive ascidian, Ciona intestinalis species complex
The vase tunicate, Ciona intestinalis species complex, has become a good model for ecological and evolutionary studies, especially those focusing on microevolution associated with rapidly changing environments. However, genome-wide genetic markers are still lacking. Here we characterized a large set of genome-wide gene-associated microsatellite markers for C. intestinalis spA (= C. robusta). Bioinformatic analysis identified 4654 microsatellites from expressed sequence tags (ESTs), 2126 of which successfully assigned to chromosomes were selected for further analysis. Based on the distribution evenness on chromosomes, function annotation and suitability for primer design, we chose 545 candidate microsatellites for further characterization. After amplification validation and variation assessment, 218 loci were polymorphic in at least one of the two populations collected from the coast of Arenys de Mar, Spain (N = 24 - 48) and Cape Town, South Africa (N = 24 - 33). The number of alleles, observed heterozygosity and expected heterozygosity ranged from two to 11, 0 to 0.833 and 0.021 to 0.818, and from two to 10, 0 to 0.879 and 0.031 to 0.845 for the Spanish and African populations, respectively. When all microsatellites were tested for cross-species utility, only 60 loci (25.8%) could be successfully amplified and all loci were polymorphic in C. intestinalis spB. A high level of genome-wide polymorphism is likely responsible for the low transferability. The large set of microsatellite markers characterized here is expected to provide a useful genome-wide resource for ecological and evolutionary studies using C. intestinalis as a model.
Data from: Microsatellite loci for dreissenid mussels (Mollusca: Bivalvia: Dreissenidae) and relatives: markers for assessing exotic and native populations
We developed and tested 14 new polymorphic microsatellite loci for dreissenid mussels, including the two species that have invaded many freshwater habitats in Eurasia and North America, where they cause serious industrial fouling damage and ecological alterations. These new loci will aid our understanding of their genetic patterns in invasive populations as well as throughout their native Ponto-Caspian distributions. Eight new loci for the zebra mussel Dreissena polymorpha and six for the quagga mussel D. rostriformis bugensis were compared with new results from six previously published loci to generate a robust molecular toolkit for dreissenid mussels and their relatives. Taxa tested include D. polymorpha , D. r. bugensis , D. r. grimmi , D. stankovici , the "living fossil" Congeria kusceri , and the dark false mussel Mytilopsis leucophaeata (the latter also is invasive). Overall, most of the 24 zebra mussel (N=583) and 13 quagga mussel (N=269) population samples conformed to Hardy-Weinberg equilibrium expectations for the new loci following Bonferroni correction. The 11 loci (eight new, three previously published) evaluated for D. polymorpha averaged 35.1 alleles and 0.72 mean observed heterozygosity per locus, and 25.3 and 0.75 for the nine loci (six new, three previously published) developed for D. r. bugensis . All but three of these loci successfully amplified the other species of Dreissena , and all but one also amplified Congeria and Mytilopsis . All species and populations tested were significantly divergent using the microsatellite data, with neighbor-joining trees reflecting their evolutionary relationships; our results reveal broad utility for resolving their biogeographic, evolutionary, population, and ecological patterns.
Data from: Heterozygosity-fitness correlations in zebra finches: microsatellite markers can be better than their reputation
Numerous studies have reported associations between heterozygosity in microsatellite markers and fitness-related traits (heterozygosity-fitness correlations, HFCs). However, it has often been questioned whether HFCs reflect general inbreeding depression, because a small panel of microsatellite markers does not reflect very well an individual's inbreeding coefficient (F) as calculated from a pedigree. Here we challenge this prevailing view. Due to chance events during Mendelian segregation, an individual's realized proportion of the genome that is identical by descent (IBD) may substantially deviate from the pedigree-based expectation (i.e. F). This Mendelian noise may result in a weak correlation between F and multi-locus heterozygosity, but this does not imply that multi-locus heterozygosity is a bad estimator of realized IBD. We examined correlations between 11 fitness-related traits measured in up to 1,192 captive zebra finches and three measures of inbreeding: (1) heterozygosity across 11 microsatellite markers, (2) heterozygosity across 1,359 SNP markers, and (3) F, based on a 5-generation pedigree. All 11 phenotypic traits showed positive relationships with measures of heterozygosity, especially traits that are most closely related to fitness. Remarkably, the small panel of microsatellite markers produced equally strong HFCs as the large panel of SNP markers, and both marker-based approaches produced stronger correlations with phenotypes than the pedigree-based F. We argue that a small panel of microsatellites with high allelic richness may better reflect an individual's realized IBD than previously appreciated, especially in species like the zebra finch, where much of the genome is inherited in large blocks that rarely experience cross-over during meiosis.
Data from: Microsatellite abundance across the Anthozoa and Hydrozoa in the phylum Cnidaria
Background: Microsatellite loci have high mutation rates and thus are indicative of mutational processes within the genome. By concentrating on the symbiotic and aposymbiotic cnidarians, we investigated if microsatellite abundances follow a phylogenetic or ecological pattern. Individuals from eight species were shotgun sequenced using 454 GS-FLX Titanium technology. Sequences from the three available cnidarian genomes (Nematostella vectensis, Hydra magnipapillata and Acropora digitifera) were added to the analysis for a total of eleven species representing two classes, three subclasses and eight orders within the phylum Cnidaria. Results: Trinucleotide and tetranucleotide repeats were the most abundant motifs, followed by hexa- and dinucleotides. Pentanucleotides were the least abundant motif in the data set. Hierarchical clustering and log likelihood ratio tests revealed a weak relationship between phylogeny and microsatellite content. Further, comparisons between cnidaria harboring intracellular dinoflagellates and those that do not, show microsatellite coverage is higher in the latter group. Conclusions: Our results support previous studies that found tri- and tetranucleotides to be the most abundant motifs in invertebrates. Differences in microsatellite coverage and composition between symbiotic and non-symbiotic cnidaria suggest the presence/absence of dinoflagellates might place restrictions on the host genome.
Data from: Rapid development and screening of microsatellite loci for Artibeus lituratus and their utility for six related species within Phyllostomidae
Microsatellites are often the marker of choice for population genetic studies at intermediate spatial and temporal scales. Developing large numbers of markers has traditionally been technically difficult and this has limited our ability to investigate evolutionary phenomena that emerge across short temporal scales. Moreover, few markers tend to successfully amplify across species boundaries. As rapid advancements in high-throughput sequencing make microsatellite development cost and time-effective, new avenues for evolutionary, population genetic, and chromosome linkage mapping research are emerging. We used a published PERL script and second-generation sequencing to rapidly and affordably develop microsatellite loci for a widespread phyllostomid bat, Artibeus lituratus, for which no markers were previously available. We used Roche FLX (Titanium) Genome Sequencing to randomly sequence ~101 Mb (255,065 unique reads) of genomic DNA for A. lituratus, within which we discovered 30100 microsatellite loci. We designed primers for 19395 loci that contained suitable flanking regions. We ordered primers for 96 loci, 90 of which produced a single PCR product in A. lituratus. We genotyped 52 loci, and 45 were polymorphic in A. lituratus. We tested cross-species amplification for 96 loci in six additional phyllostomid species: A. planirostris, A. fimbriatus, A. phaeotis, Enchisthenes hartii, Sturnira lilium, and Carollia perspicillata. Cross-species amplification was successful for at least one species for 87 loci (A. fimbriatus), and in all species at least 66 loci amplified. These markers will facilitate future work on these seven species, but also illustrate the utility of this high-throughput method for development of primers across many species simultaneously.
Data from: Sex, size and timing: sampling design for reliable population genetics analyses using microsatellite data
1. Population genetics is used in a wide variety of fields such as ecology and biodiversity conservation. How estimated genetic characteristics of natural populations can be influenced by the sampling design has been a long-standing concern. Multiple simulation and empirical studies illustrated the influence of both sample size and polymorphism of markers. However, our review of studies on butterfly population genetics indicates no consensus on sample size for the estimation of genetic diversity or differentiation. Furthermore, other aspects of sampling design (sex ratio and timing of sampling) were not addressed and their potential impact on genetic parameter estimates rarely explored. 2. Using a large empirical dataset (with spatial and temporal replicates) collected on a butterfly species, Boloria aquilonaris, as well as simulated datasets reflecting (1) three scenarios of migration-genetic drift equilibrium and (2) one scenario of parameter stabilization after 100,000 generations, we quantified the impacts of three aspects of genetic sampling design (namely sample size, sex ratio, and timing of sampling) on the estimation of allele frequencies and its potential downstream impact on the estimation of genetic parameters. 3. With empirical data, we found that sample size and timing of sampling strongly affected the accuracy of allele frequencies and the downstream analyses, while sex ratio did not. Our results were consistent across spatial and temporal replicates. Also, with simulated data, we showed that the genetic sampling design had limited effect in systems where dispersal outweighs genetic drift, while it can have major consequences on our understanding of the genetic diversity and population differentiation in systems dominated by genetic drift (such as most study systems with conservation concerns). 4. We advocate for careful consideration of all aspects of the sampling design in population genetics studies, i.e. a sufficient number of samples, while ensuring similar sex ratio among sampling locations and collecting with timing appropriate to the question under study. This is particularly important when the study aims at species conservation.
Data from: Breakdown of phylogenetic signal: a survey of microsatellite densities in 454 shotgun sequences from 154 non model eukaryote species
Microsatellites are ubiquitous in Eukaryotic genomes. A more complete understanding of their origin and spread can be gained from a comparison of their distribution within a phylogenetic context. Although information for model species is accumulating rapidly, it is insufficient due to a lack of species depth, thus intragroup variation is necessarily ignored. As such, apparent differences between groups may be overinflated and generalizations cannot be inferred until an analysis of the variation that exists within groups has been conducted. In this study, we examined microsatellite coverage and motif patterns from 454 shotgun sequences of 154 Eukaryote species from eight distantly related phyla (Cnidaria, Arthropoda, Onychophora, Bryozoa, Mollusca, Echinodermata, Chordata and Streptophyta) to test if a consistent phylogenetic pattern emerges from the microsatellite composition of these species. It is clear from our results that data from model species provide incomplete information regarding the existing microsatellite variability within the Eukaryotes. A very strong heterogeneity of microsatellite composition was found within most phyla, classes and even orders. Autocorrelation analyses indicated that while microsatellite contents of species within clades more recent than 200 Mya tend to be similar, the autocorrelation breaks down and becomes negative or non-significant with increasing divergence time. Therefore, the age of the taxon seems to be a primary factor in degrading the phylogenetic pattern present among related groups. The most recent classes or orders of Chordates still retain the pattern of their common ancestor. However, within older groups, such as classes of Arthropods, the phylogenetic pattern has been scrambled by the long independent evolution of the lineages.
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Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.