FST Estimates Research Articles

Generation of a neutral FST baseline for testing local adaptation on gill raker number within and between European whitefish ecotypes in the Baltic Sea basin.

Divergent selection at ecologically important traits is thought to be a major factor driving phenotypic differentiation between populations. To elucidate the role of different evolutionary processes shaping the variation in gill raker number of European whitefish (Coregonus lavaretus sensu lato) in the Baltic Sea basin, we assessed the relationships between genetic and phenotypic variation among and within three whitefish ecotypes (sea spawners, river spawners and lake spawners). To generate expected neutral distribution of FST and to evaluate whether highly variable microsatellite loci resulted in deflated FST estimates compared to less variable markers, we performed population genetic simulations under finite island and hierarchical island models. The genetic divergence observed among (FCT = 0.010) and within (FST = 0.014-0.041) ecotypes was rather low. The divergence in gill raker number, however, was substantially higher between sea and river spawners compared to observed microsatellite data and simulated neutral baseline (PCT > FCT ). This suggests that the differences in gill raker number between sea and river spawners are likely driven by divergent natural selection. We also found strong support for divergent selection on gill raker number among different populations of sea spawners (PST > FST ), most likely caused by highly variable habitat use and diverse diet. The putative role of divergent selection within lake spawners initially inferred from empirical microsatellite data was not supported by simulated FST distributions. This work provides a first formal test of divergent selection on gill raker number in Baltic whitefish, and demonstrates the usefulness of population genetic simulations to generate informative neutral baselines for PST -FST analyses helping to disentangle the effects of stochastic evolutionary processes from natural selection.

Development of genomic SSR markers and genetic diversity analysis in cultivated radish (Raphanus sativus L.)

Radish (Raphanus sativus L.) is a major vegetable cultivated worldwide. As a member of the family Brassicaceae, this species has diverse morphological characteristics in root. Radish cultivars have been classified based on morphological traits, including root shape and color. Despite its economic importance in Asia, genomic research in radish is less well developed relative to Brassica rapa, a close relative of radish. In this study, we developed genomic simple sequence repeat (SSR) markers using a SSR-enriched library and investigated genetic diversity in a collection of 144 radish cultivars. A total of 237 primer pairs for SSRs were designed and 184 (77.6%) primer pairs produced PCR amplicons. Of these, we selected 27 SSR markers (14.7%) based on polymorphism in a subset of 11 cultivars and then used to assess genetic relationships in the germplasm panel. For these markers, the number of alleles per marker ranged from 2 to 18 with an average of 7.77 alleles and the polymorphism information content (PIC) values ranged from 0.491 to 0.906. The estimates of pairwise F st revealed significant genetic differentiation between the five market classes of 135 radish cultivars (74 big, 15 small, 29 young, 12 Altari, and 5 processing). Clustering analysis using NTSYS-pc and STRUCTURE software also found that the 74 big radishes were divided into 5–7 clusters. In addition, all 27 SSR markers were able to differentiate 64 big radish cultivars based on the UPGMA dendrogram and each of the 23 markers independently identified 1 to 17 big radish cultivars. These results suggest that cultivated radishes have different patterns of genetic variation and breeding practices should be a driving force for the genetic differentiation between and within market classes. The SSR markers developed in this study will be a useful resource for genetic study and protection of plant breeder’s intellectual property right through cultivar identification.

Genetic variability and bottleneck detection of four Tricholoma matsutake populations from northeastern and southwestern China.

The excessive commercial collection of matsutake mushrooms can lead to extreme reduction of population size, which may cause genetic bottleneck and decrease genetic diversity of Tricholoma matsutake. Here, six polymorphic microsatellite loci markers were used to examine the genetic diversity of four natural T. matsutake populations from two main producing regions of China. The minimum combinations of four loci were able to discriminate total 86 sampled individuals with distinctive multilocus genotypes. Our analysis of molecular variance (AMOVA) revealed that about 80% and 20% of the overall genetic variation were respectively partitioned within and among populations. The principal-coordinate analyses (PCA) distinguished the four tested populations into three genetic clusters, each of which was correlated with respective endemic host plants on a geographical basis. The AMOVA, PCA and pairwise population FST estimates consistently displayed the same genetic divergence patterns and spatial structure of T. matsutake mediated by host plants in China. The significant heterozygosity excesses demonstrated that a recent genetic bottleneck occurred in each population tested. The complementary M-ratio test indicated past genetic bottleneck events over longer periods. Only four individuals were identified as putative first generation migrants within northeastern China, which implies restricted interpopulation gene flow in T. matsutake. We discuss that the significant genetic differentiation among populations of T. matsutake is most likely a function of host adaptation, host specificity, genetic bottleneck, limited dispersal and habitat fragmentation.

Analysis of genetic variability and differentionin of stellate sturgeon, Acipenser stellatus (Pallas, 1771), in the North (Volga and Ural Rivers) and South Caspian Sea (estuary of Sefidrud)

In total, 140 samples of adult stellate sturgeon Acipenser stellatus were collected at three sites Northern (Volga and Ural Rivers) and Southern Caspian Sea (estuary of Sefidrud- Iran). Fifteen sets of microsatellite primers were tested on genomic DNA. Ten primer sets revealing polymorphic loci were used to analyze the genetic variation found in adults of the stellate sturgeon populations. The analyses revealed that the average of alleles per locus was 14.33 and all the sampled regions contained private alleles. The observed and expected heterozygosity averaged 0.677 and 0.871, respectively. Average of Fis and Fit were 0.225 and 0.250 respectively. Fst, Rst and gene flow estimates in AMOVA indicated significant genetic differentiation among regions, indicating that the populations were divergent. The genetic distance between populations indicating that the genetic difference among populations is pronounced. These results together with highly significant Rst of genotypic differences between these pairs of collections support the existence of different genetic populations along the Caspian Sea coasts.

Genetic diversity, population structure and marker trait associations for seed quality traits in cotton (Gossypium hirsutum).

Cottonseed contains 16% seed oil and 23% seed protein by weight. High levels of palmitic acid provides a degree of stability to the oil, while the presence of bound gossypol in proteins considerably changes their properties, including their biological value. This study uses genetic principles to identify genomic regions associated with seed oil, protein and fibre content in upland cotton cultivars. Cotton association mapping panel representing the US germplasm were genotyped using amplified fragment length polymorphism markers, yielding 234 polymorphic DNA fragments. Phenotypic analysis showed high genetic variability for the seed traits, seed oil range from 6.47-25.16%, protein from 1.85-28.45% and fibre content from 15.88-37.12%. There were negative correlations between seed oil and protein content.With reference to genetic diversity, the average estimate of FST was 8.852 indicating a low level of genetic differentiation among subpopulations. The AMOVA test revealed that variation was 94% within and 6% among subpopulations. Bayesian population structure identified five subpopulations and was in agreement with their geographical distribution. Among the mixed models analysed, mixed linear model (MLM) identified 21 quantitative trait loci for lint percentage and seed quality traits, such as seed protein and oil. Establishing genetic diversity, population structure and marker trait associations for the seed quality traits could be valuable in understanding the genetic relationships and their utilization in breeding programmes.

Genetic variation and population structure of marbled sole Pleuronectes yokohamae and cresthead flounder P. schrenki in Japan inferred from mitochondrial DNA analysis

Nucleotide sequence analysis in the first half of the mitochondrial control region was used to estimate genetic variation and population structure of marbled sole Pleuronectes yokohamae and cresthead flounder Pleuronectes schrenki, obtained from 10 localities in Japan. Overall estimate of pairwise population FST and NJ tree suggested genetic distinction between P. yokohamae and P. schrenki. SAMOVA also demonstrated two distinct genetic groups of the samples, MS (marbled sole, Honshu and southernmost Hokkaido) and CF(cresthead flounder, Hokkaido), which was pertinent to the natural range of P. yokohamae and P. schrenki, respectively. However, the haplotypes common to P. yokohamae and P. schrenki were found in all four samples of the CF group and two of six samples of the MS group. Haplotype and nucleotide diversities were high within MS and CF groups, and the mismatch distribution analysis showed a bimodal profile in both groups, suggesting secondary contact between allopatrically evolved MS and CF groups. Thus, the observed haplotype sharing between two species might have been the consequence of interspecific hybridization after their divergence. In addition, FST estimates and Mantel test suggested that the population structure of P. yokohamae might have been influenced by low or restricted gene flow with isolation by distance, whereas no such population structuring was implied for P. schrenki. The observed difference in population structuring between two species was surmised by the difference of migration character.

Genetic diversity and population structure of the ark shell Scapharca broughtonii along the coast of China based on microsatellites

As a commercially important species in East Asia, the natural resources of Scapharca broughtonii have been suffering from severe population decline across its main habitats. In China, recovery efforts for S. broughtonii are in progress. To provide scientific bases for fisheries management and conservation program, genetic diversity and population structure of seven wild populations of S. broughtonii from the northern China coast was assessed using seven microsatellite loci in this study. High genetic diversity was present in all the seven populations, as observed in mean allelic richness per locus (11.3–12.5), and average expected heterozygosity (0.835–0.867). No significant difference in allelic richness or expected heterozygosity was observed among the seven populations. Pairwise FST estimates and NJ tree topologies based on DC distances indicated that the seven populations fell into two groups, showing a clear division between the populations from the south and north of the Shandong Peninsula. Genetic differentiation was further analyzed using AMOVA and assignation tests. Genetic barrier analysis using Monmonier algorithm also confirmed that the Shandong Peninsula was the putative barrier separating the northern and southern populations. In addition, marine currents probably play an important role in high gene flow among three populations from the same marine gyre.

Assessing genetic diversity of three Tunisian dromedary camel (Camelus dromedarius) sub populations using microsatellite markers

One of the main tasks of the PROCAMED project is to promote research on genetics of dromedary camel. In this regard, and to evaluate the genetic diversity among Tunisian dromedary camel, a total of 62 blood samples were collected from unrelated animals in three different regions (Tataouine, Medenine and Kebili) and belonging to three sub-populations (Ourdhaoui Médenine, Ourdhaoui Tataouine and Merzougui) defined on the basis of morphologic and geographic criterions. From seven microsatellite markers used only four were successfully amplified resulting in a total of 26 alleles observed in the three sub-populations with a mean number of alleles (MNA) of 6.5. Unbiased expected heterozygosity (He) ranged from 0.76 to 0.84 whereas the observed heterozygosity was absolute (Ho = 1) and an excess of heterozygotes was observed in the three groups for all four loci. The mean estimates of the fixation index FST was 0.052 showing a moderate genetic structure between the different sub-populations. Little differentiation was observed between Ourdhaoui Médenine and Merzougui sub-populations, compared to Ourdhaoui Tataouine sub-population which seems to be more established. The results showed the limits of camel classification on the basis of only morphologic and regional distribution criterions.

Mixed stock analysis of a resident green turtle, Chelonia mydas, population in New Caledonia links rookeries in the South Pacific

Context Migratory species are known to pose a challenge for conservation because it is essential to understand their complex life history in order to implement efficient conservation actions. Aims In New Caledonia, large seagrass habitats in the Grand Lagon Sud (GLS) are home to resident green turtles (Chelonia mydas) of unknown origins. To assess the stock composition in the GLS, 164 foraging turtles were sampled for genetic analysis of ~770 base pairs of the mitochondrial DNA (mtDNA) control region. Methods Foraging turtles ranging in size from 48.0 to 108.4 cm curved carapace length were captured at five different sites within the GLS between September 2012 and December 2013. To provide baseline data for mixed stock analysis, published data from rookeries were used in addition to 105 samples collected at rookeries in the d’Entrecasteaux Islands and Chesterfield Islands in New Caledonia and at Malekula Island in Vanuatu. Exact tests of population differentiation and pairwise FST estimates were used to test for differences in mtDNA haplotype frequencies. Key results These analyses indicated that rookeries in the d’Entrecasteaux Islands and Vanuatu form unique management units and that the Chesterfield Islands rookeries are linked to the Coral Sea management unit. Mixed stock analysis indicated the highest proportion (mean = 0.63) of foraging turtles originate from the d’Entrecasteaux stock. Conclusions The larger contribution is estimated to be from a large rookery from New Caledonia, but smaller contributions are suggested from other rookeries in the South Pacific. Implications Marine conservation policies in New Caledonia need to consider the links between the foraging and nesting populations of C. mydas in New Caledonia and other rookeries and foraging grounds in the Coral Sea.

Detecting signatures of selection in nine distinct lines of broiler chickens.

Modern commercial chickens have been bred for one of two specific purposes: meat production (broilers) or egg production (layers). This has led to large phenotypic changes, so that the genomic signatures of selection may be detectable using statistical techniques. Genetic differentiation between nine distinct broiler lines was calculated using Weir and Cockerham's pairwise FST estimator for 11003 genome-wide markers to identify regions showing evidence of differential selection across lines. Differentiation measures were averaged into overlapping sliding windows for each line, and a permutation approach was used to determine the significance of each window. A total of 51 regions were found to show significant differentiation between the lines. Several lines were consistently found to share significant regions, suggesting that the pattern of line divergence is related to selection for broiler traits. The majority of the 51 regions contain QTL relating to broiler traits, but only five of them were found to be significantly enriched for broiler QTL, including a region on chromosome 27 containing 39 broiler QTL and 114 genes. Additionally, a number of these regions have been identified by other selection mapping studies. This study has identified a large number of potential selection signatures, and further tests with higher-density marker data may narrow these regions down to individual genes.

Leishmania donovani populations in Eastern Sudan: temporal structuring and a link between human and canine transmission.

BackgroundVisceral leishmaniasis (VL), caused by the members of the Leishmania donovani complex, has been responsible for devastating VL epidemics in the Sudan. Multilocus microsatellite and sequence typing studies can provide valuable insights into the molecular epidemiology of leishmaniasis, when applied at local scales. Here we present population genetic data for a large panel of strains and clones collected in endemic Sudan between 1993 and 2001.MethodsGenetic diversity was evaluated at fourteen microsatellite markers and eleven nuclear sequence loci across 124 strains and clones.ResultsMicrosatellite data defined six genetic subpopulations with which the nuclear sequence data were broadly congruent. Pairwise estimates of FST (microsatellite) and KST (sequence) indicated small but significant shifts among the allelic repertoires of circulating strains year on year. Furthermore, we noted the co-occurrence of human and canine L. donovani strains in three of the six clusters defined. Finally, we identified widespread deficit in heterozygosity in all four years tested but strong deviation from inter-locus linkage equilibrium in two years.ConclusionsSignificant genetic diversity is present among L. donovani in Sudan, and minor population structuring between years is characteristic of entrenched, endemic disease transmission. Seasonality in vector abundance and transmission may, to an extent, explain the shallow temporal clines in allelic frequency that we observed. Genetically similar canine and human strains highlight the role of dogs as important local reservoirs of visceral leishmaniasis.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-014-0496-4) contains supplementary material, which is available to authorized users.

Where is the friend's home?

Where is the friend's home?

Population genetic structure and demographic history of Pacific blue sharks (Prionace glauca) inferred from mitochondrial DNA analysis

Cosmopolitan pelagic species often show shallow genetic divergence and weak, or no, genetic structure across a species’ range. However, there have been few such genetic studies for pelagic sharks. The pelagic blue shark (Prionace glauca) has a broad circumglobal distribution in tropical and temperate oceans. To investigate the population genetic structure and demographic history of this species, we analysed variation in the mitochondrial cytochrome b sequence for a total of 404 specimens collected from 10 locations across the Indo-Pacific region. The observed genetic diversities were comparable among sampling locations (h=0.77–0.87; π=0.17–0.23%). Spatial analysis of molecular variance (SAMOVA), pairwise ΦST and conventional FST estimates, and analysis of isolation with migration indicated weak or no genetic differentiation of this species across the Indo-Pacific region. The results of three phylogeographic analyses (i.e. mismatch distribution and parsimony haplotype network analyses and a neutrality test) suggested that the Pacific blue shark had historically experienced a sudden population expansion. These results, coupled with the biological properties of this species, imply that historical climate fluctuation has had only a minor effect on the genetic structuring of the blue shark.

Genetic diversity and effect of natural selection at apical membrane antigen-1 (AMA-1) among Iranian Plasmodium vivax isolates

Apical membrane antigen-1 (AMA-1) of Plasmodium vivax Grassi et Feletti, 1890 is a promising malaria vaccine candidate. However, antigenic variation is a major problem to design a universal malaria vaccine. Hence, detailed understanding of the pvama-1 gene polymorphism can provide conductive information on this potential vaccine component. Therefore, this study investigated the extent of genetic polymorphisms at domain I (DI), DII and partial DIII of AMA-1 among Iranian P. vivax isolates. Out of 107 blood samples, 92 were analysed based on the quality of the sequencing data. The sequences were classified into 53 haplotypes. Amino acid changes were observed at 31 positions that 17 were located at DI, 11 were at DII and the rest of them (3 positions) were at DIII. Thus, codon polymorphisms at DI were found to be higher than DII. Also, five of these polymorphic codons (D242E, T374P, S389R, Y391F, I395F) were novel and have not been reported yet. Neutrality analysis by using the dN-dS difference (the difference between the rate of non-synonymous and synonymous mutations) showed a negative diversifying selection at DI, DII and across the length of both domains. The potential B-cell epitopes were found in 5 regions of the PvAMA-1 with 10 mutation sites (E145A, K188N, E189N/K/D, K190Q/E, P210S, E227V, D242E, R249H, G253E, K352E), whereas only one mutation (G288E) has been detected in intrinsically unstructured/disordered regions. Fixation index (Fst) estimation between Iranian and Indian isolates (0.0131) indicated a significant low genetic differentiation. Distribution of the polymorphic sites and IURs mapped on a three dimensional structure of PvAMA-1 showed that these regions were located at two opposite faces of the molecule. In conclusion, the results have significant value in the design and development of a malaria vaccine based on this antigen.

Worldwide F(ST) estimates relative to five continental-scale populations.

We estimate the population genetics parameter (also referred to as the fixation index) from short tandem repeat (STR) allele frequencies, comparing many worldwide human subpopulations at approximately the national level with continental-scale populations. is commonly used to measure population differentiation, and is important in forensic DNA analysis to account for remote shared ancestry between a suspect and an alternative source of the DNA. We estimate comparing subpopulations with a hypothetical ancestral population, which is the approach most widely used in population genetics, and also compare a subpopulation with a sampled reference population, which is more appropriate for forensic applications. Both estimation methods are likelihood-based, in which is related to the variance of the multinomial-Dirichlet distribution for allele counts. Overall, we find low values, with posterior 97.5 percentiles when comparing a subpopulation with the most appropriate population, and even for inter-population comparisons we find . These are much smaller than single nucleotide polymorphism-based inter-continental estimates, and are also about half the magnitude of STR-based estimates from population genetics surveys that focus on distinct ethnic groups rather than a general population. Our findings support the use of up to 3% in forensic calculations, which corresponds to some current practice.

Heritability and quantitative genetic divergence of serotiny, a fire-persistence plant trait.

Although it is well known that fire acts as a selective pressure shaping plant phenotypes, there are no quantitative estimates of the heritability of any trait related to plant persistence under recurrent fires, such as serotiny. In this study, the heritability of serotiny in Pinus halepensis is calculated, and an evaluation is made as to whether fire has left a selection signature on the level of serotiny among populations by comparing the genetic divergence of serotiny with the expected divergence of neutral molecular markers (QST-FST comparison). A common garden of P. halepensis was used, located in inland Spain and composed of 145 open-pollinated families from 29 provenances covering the entire natural range of P. halepensis in the Iberian Peninsula and Balearic Islands. Narrow-sense heritability (h(2)) and quantitative genetic differentiation among populations for serotiny (QST) were estimated by means of an 'animal model' fitted by Bayesian inference. In order to determine whether genetic differentiation for serotiny is the result of differential natural selection, QST estimates for serotiny were compared with FST estimates obtained from allozyme data. Finally, a test was made of whether levels of serotiny in the different provenances were related to different fire regimes, using summer rainfall as a proxy for fire regime in each provenance. Serotiny showed a significant narrow-sense heritability (h(2)) of 0·20 (credible interval 0·09-0·40). Quantitative genetic differentiation among provenances for serotiny (QST = 0·44) was significantly higher than expected under a neutral process (FST = 0·12), suggesting adaptive differentiation. A significant negative relationship was found between the serotiny level of trees in the common garden and summer rainfall of their provenance sites. Serotiny is a heritable trait in P. halepensis, and selection acts on it, giving rise to contrasting serotiny levels among populations depending on the fire regime, and supporting the role of fire in generating genetic divergence for adaptive traits.

Divergent selection in low and high elevation populations of a perennial herb in the Swiss Alps

Mountain plant species with wide elevational ranges are expected to be exposed to different selection pressures at low and high elevation. Estimating the extent of genetic population differentiation contributes to our understanding of selective forces shaping phenotypic variation of plants in response to changing climate conditions. Using a common garden experiment, we measured narrow-sense heritability (h 2) and quantitative trait differentiation (Q ST) in several growth-related, reproductive and phenological traits among low and high elevation populations of the semi-dry grassland species Ranunculus bulbosus from the Swiss Alps. Q ST values were compared to neutral genetic differentiation (F ST) based on AFLP markers and indicated divergent selection in most traits among all populations as well as among low and high elevation populations separately. Furthermore, pairwise Q ST and F ST estimates were not correlated suggesting that neutral marker differentiation is not a valuable proxy for quantitative trait differentiation. Neutral molecular differentiation increased with geographical distance whereas quantitative genetic differentiation did not follow an isolation by distance pattern. Plant traits did mostly not differ among low and high populations and pairwise Q ST–F ST comparisons indicated no divergent selection between the two elevations. Differing levels of trait differentiation in low and high elevation populations, however, indicated that different selective forces acted on plants at contrasting elevations suggesting that selection regimes might alter under climate warming.

Genetic diversity and population structure of long-tailed macaque (Macaca fascicularis) populations in Peninsular Malaysia

The genetic diversity and structure of long-tailed macaques (Macaca fascicularis) in Peninsular Malaysia, a widely used non-human primate species in biomedical research, have not been thoroughly characterized. Thirteen sites of wild populations of long-tailed macaques representing six states were sampled and analyzed with 18 STR markers. The Sunggala and Penang Island populations showed the highest genetic diversity estimates, while the Jerejak Island population was the most genetically discrete due to isolation from the mainland shelf. Concordant with pairwise F(st) estimates, STRUCTURE analyses of the seven PCA-correlated clusters revealed low to moderate differentiation among the sampling sites. No association between geographic and genetic distances exists, suggesting that the study sites, including island study sites, are genetically if not geographically contiguous. The status of the genetic structure and composition of long-tailed macaque populations require further scrutiny to develop this species as an important animal model in biomedical research.

Large effective population sizes and high levels of gene flow between subpopulations of Lilium cernuum (Liliaceae)

The Baekdudaegan, a mountain range that runs north to south along the Korean Peninsula, has been suggested to harbor important glacial refugia for boreal and temperate plant species. A series of allozyme-based genetic studies supports this trend. A large effective population size (Ne) is suggested as one of major factors contributing to maintaining moderate or high levels of within-population genetic variation in these plant species. To test this hypothesis, we examined the levels and patterns of allozyme diversity, tested recent bottlenecks, and estimated recent migration rates in 10 subpopulations (collected within a distance of ca. 640 m) of the boreal Lilium cernuum at Mt. Deokhang, in the central part of the Baekdudaegan. We found high levels of within-population genetic variation as well as a low between-population genetic differentiation (He = 0.206 and FST = 0.019). Based on the FST estimate and mean recent migration rate, we approximately calculated a total effective population size of 508 across 10 subpopulations. Consistent with this, we found no evidence of recent bottlenecks in the subpopulations. This study reveals that subpopulations of L. cernuum at Mt. Deokhang are effectively large (on the order of hundreds), and that high levels of gene flow occur among them, probably due to the species' high potential for seed dispersal. These demographic and life-history traits, coupled with its high levels of genetic diversity, suggests that this cold-adapted species would have found large refugial areas in these mountains (i.e., macrorefugia) during the Last Glacial Maximum.

Genetic Differentiation among Maruca vitrata F. (Lepidoptera: Crambidae) Populations on Cultivated Cowpea and Wild Host Plants: Implications for Insect Resistance Management and Biological Control Strategies

Maruca vitrata Fabricius (Lepidoptera: Crambidae) is a polyphagous insect pest that feeds on a variety of leguminous plants in the tropics and subtropics. The contribution of host-associated genetic variation on population structure was investigated using analysis of mitochondrial cytochrome oxidase 1 (cox1) sequence and microsatellite marker data from M. vitrata collected from cultivated cowpea (Vigna unguiculata L. Walp.), and alternative host plants Pueraria phaseoloides (Roxb.) Benth. var. javanica (Benth.) Baker, Loncocarpus sericeus (Poir), and Tephrosia candida (Roxb.). Analyses of microsatellite data revealed a significant global FST estimate of 0.05 (P≤0.001). The program STRUCTURE estimated 2 genotypic clusters (co-ancestries) on the four host plants across 3 geographic locations, but little geographic variation was predicted among genotypes from different geographic locations using analysis of molecular variance (AMOVA; among group variation −0.68%) or F-statistics (F ST Loc = −0.01; P = 0.62). These results were corroborated by mitochondrial haplotype data (φSTLoc = 0.05; P = 0.92). In contrast, genotypes obtained from different host plants showed low but significant levels of genetic variation (F ST Host = 0.04; P = 0.01), which accounted for 4.08% of the total genetic variation, but was not congruent with mitochondrial haplotype analyses (φSTHost = 0.06; P = 0.27). Variation among host plants at a location and host plants among locations showed no consistent evidence for M. vitrata population subdivision. These results suggest that host plants do not significantly influence the genetic structure of M. vitrata, and this has implications for biocontrol agent releases as well as insecticide resistance management (IRM) for M. vitrata in West Africa.