Historical vicariance and male-mediated gene flow in the toad-headed lizards Phrynocephalus przewalskii

Using mitochondrial and microsatellite DNA data and a population genetic approach, we tested male‐mediated gene flow in the toad‐headed lizards Phrynocephalus przewalskii. The mitochondrial DNA (ND2 gene), on the one hand, revealed two major lineages and a strong population genetic structure (F_ST = 0.692; F_ST′ = 0.995). The pairwise differences between the two lineages ranged from 2.1% to 6.4% and the geographical division of the two lineages coincided with a mountain chain consisting of the Helan and Yin Mountains, suggesting a historical vicariant pattern. On the other hand, the nuclear microsatellite DNA revealed a significant but small population genetic structure (F_ST = 0.017; F_ST′ = 0.372). The pairwise F_ST among the nine populations examined with seven microsatellite DNA loci ranged from 0.0062 to 0.0266; the assignment test failed to detect any naturally occurring population clusters. Furthermore, the populations demonstrated a weak isolation by distance and a northeast to southwest clinal variation, rather than a vicariant pattern. A historical vicariant event followed by male‐mediated gene flow appears to be the best explanation for the data. Approximately 2–5 Ma, climatic change may have created an uninhabitable zone along the Helan‐Yin mountain chain and initiated the divergence between the two mitochondrial lineages. With further climatic changes, males were able to disperse across the mountain chain, causing sufficient gene flow that eventually erased the vicariant pattern and drastically reduced the population genetic structure, while females remained philopatric and maintained the mitochondrial DNA (mtDNA) divergence. Although polygyny mating system and female philopatry may partially contribute to the reduced movement of females, other hypotheses, such as female intrasexual aggression, should also be explored.     

Isolation and characterization of microsatellite loci in the flat‐headed bat (Tylonycteris pachypus)

Microsatellite loci were developed in the flat‐headed bat (Tylonycteris pachypus) from genomic DNA using an enriched library method. Nine loci were tested on 48 individuals sampled from Guangxi Province, China. The mean number of observed alleles per locus was 6.4 (range 4–12). Observed and expected heterozygosity values ranged from 0.24 to 0.83 and from 0.30 to 0.89, respectively. One locus revealed significant departure from Hardy–Weinberg equilibrium and no significant linkage disequilibrium was detected between loci pairs. These markers will be used to examine genetic structure and parentage analysis in this species.     

Genetic evidence for male‐biased dispersal in the Qinghai toad‐headed agamid Phrynocephalus vlangalii and its potential link to individual social interactions

Sex‐biased dispersal has profound impacts on a species' biology and several factors have been attributed to its evolution, including mating system, inbreeding avoidance, and social complexity. Sex‐biased dispersal and its potential link to individual social interactions were examined in the Qinghai toad‐headed agamid (Phrynocephalus vlangalii). We first determined the pattern of sex‐biased dispersal using population genetic methods. A total of 345 specimens from 32 sites in the Qaidam Basin were collected and genotyped for nine microsatellite DNA loci. Both individual‐based assignment tests and allele frequency‐based analyses were conducted. Females revealed much more genetic structure than males and all results were consistent with male‐biased dispersal. First‐generation migrants were also identified by genetic data. We then examined eight social interaction‐related morphological traits and explored their potential link to sex‐biased dispersal. Female residents had larger heads and longer tails than female migrants. The well‐developed signal system among females, coupled with viviparity, might make remaining on natal sites beneficial, and hence promote female philopatry. Dominant females with larger heads were more likely to stay. Contrary to females, male migrants had larger heads and belly patches than residents, suggesting that dispersal might confer selective advantages for males. Such advantages may include opportunities for multiple mating and escaping from crowded sites. Large belly patches and several other morphological traits may assist their success in obtaining mates during dispersal. Furthermore, a relatively high relatedness (R = 0.06) among females suggested that this species might have rudimentary social structure. Case studies in “less” social species may provide important evidence for a better understanding of sex‐biased dispersal.     

Isolation and characterization of variable microsatellite loci in Lilium philadelphicum (Liliaceae)

Here we describe the characterization of six polymorphic microsatellite loci for Lilium philadelphicum (Liliaceae). Polymorphism levels ranged from 7 to 30 alleles per locus with a mean number of 15 alleles per locus. Observed heterozygosity (H_O) ranged from 0.17 to 0.82 and did not deviate from Hardy–Weinberg expectations in the three western Montana populations included in the analysis. These loci are proving useful in studying gene flow between populations of this species distributed across its range in North America.     

Isolation and characterization of microsatellite loci from rock shell, Thais clavigera

Imposex (superimposition of male genital organs on female phenotype) of the rock shell or whelk, Thais clavigera, shows typical evidence of endocrine disruption by organotin compounds within inter-tidal zones polluted by such compounds. It will be informative to see how low fertility caused by imposex of this species finally affects the genetic diversity of polluted populations. For future use in population genetic research of the rock shell, we report the isolation and characteristics of 11 highly polymorphic microsatellite markers with a mean of 11.7 alleles per locus. We observed heterozygosities of these sequences ranging from 0.43 to 0.95. These markers will be useful for future ecological genetic studies of rock shell.     

Isolation and characterization of microsatellite loci in Merluccius australis and cross-species amplification

Eight novel and two heterologous microsatellite pairs of primers are presented for the Austral hake (Merluccius australis), representing the first microsatellite markers available for this species. Loci were characterized for 50 individuals from two populations in South America (Argentinean and Chilean coasts). All loci were polymorphic within M. australis (5 to 30 alleles per locus; observed heterozygosity between 0.320 and 0.840), and therefore useful for population genetic studies within the species. Cross-species transferability was tested for 100 individuals from four additional species within the Merluccius genus (M. albidus, M. bilinearis, M. gayi and M. hubbsi), and results indicate that most of these primers pairs will likely be useful for population genetic studies on Merluccius species.     

Isolation and characterization of microsatellite loci in Penstemon rostriflorus (Plantaginaceae) and cross‐species amplification

Eight novel microsatellite primer pairs are presented for Penstemon rostriflorus, representing the first microsatellite markers available for this genus. Loci were characterized for 20 individuals from two populations in the Great Basin, USA. All loci are polymorphic within P. rostriflorus (seven to 13 alleles per locus; observed heterozygosity between 0.40 and 0.95), and therefore useful for population genetic studies within the species. Cross‐species transferability was tested on 40 additional species of Penstemon, and results indicate that these primers pairs will likely be useful for population genetic studies on many Penstemon species.     

Microsatellite DNA markers for three toad-headed lizard species (Phrynocephalus vlangalii, P. przewalskii and P. guttatus)

To assess the impact of natural landscapes on the population structure of lizards, 10 polymorphic microsatellite DNA markers were developed for the Qinghai toad-headed lizard, Phrynocephalus vlangalii. The number of alleles at these informative loci ranged from four to 28. The novel markers and those previously developed for Phrynocephalus przewalskii were cross-tested among three toad-headed lizard species P. vlangalii, P. przewalskii and P. guttatus. A high cross-utility rate of more than 58% was observed among these three species. These markers are expected to be useful tools for taxonomic considerations as well as population genetic analysis and future conservation management.     

Variation of 15 autosomal microsatellite DNA loci in the Russian population

The allele frequencies of 15 autosomal STR loci (D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, D7S820, D16S539, D2S1338, D8S1179, D21S11, D18S51, and D19S433) used in forensic medicine were determined for the Russian population of European Russia (N = 176). The power of discrimination (PD) and power of exclusion (PE) of the system of the 15 STR loci were 0.999 999 999 999 999 986 and 0.999 999 331 310 171 000, respectively. The allele and genotype frequency distributions in the Russian population corresponded to the Hardy-Weinberg equilibrium. The D2S1338, D18S51, D21S11, and FGA loci were identified as the most informative markers for the Russian population and proposed as a reference for forensic studies in the Russian Federation.     

Isolation and characterization of 49 polymorphic microsatellite loci in the ayu,Plecoglossus altivelis

A total of 49 novel polymorphic microsatellite markers in the ayu fish, Plecoglossus altivelis, were successfully isolated and characterized. The number of alleles per locus, observed heterozygosity, and expected heterozygosity ranged from two to 25 (11.3 on average), from 0.125 to 1.000 (0.648 on average), and from 0.123 to 0.957 (0.751 on average), respectively. These microsatellite markers will be useful for both studying population structure and identifying quantitative trait loci that control evolutionarily and economically important traits of ayu.     

Isolation and characterization of five microsatellite loci in an ectomycorrhizal fungus Laccaria laccata

Laccaria laccata is an early successional ectomycorrhizal fungus. We isolated five polymorphic microsatellite loci from L. laccata using a dual‐suppression polymerase chain reaction technique. The number of alleles per locus ranged from three to six. The observed and expected heterozygosities ranged from 0.269 to 0.462, and 0.249 to 0.775, respectively. These microsatellite markers would be valuable molecular tools for population genetic studies of L. laccata.     

Isolation and characterization of 16 microsatellite loci in the Great Tit Parus major

Six dinucleotide, three trinucleotide and seven tetranucleotide microsatellite loci developed for the great tit Parus major are presented. Thirty individual birds were screened at each locus. Loci were polymorphic (four to 19 alleles per locus). These markers provide a system to study paternity, genetic diversity in natural populations, gene flow, dispersal and inbreeding.     

Isolation and characterization of microsatellite DNA markers in the grass Poa alpina L.

The important fodder grass Poa alpina L. occurs at several ploidy levels with common aneuploidy. We isolated and characterized five polymorphic microsatellite markers for the study of molecular genetic variation of this species. As first examples of the value of the developed markers for population genetic analyses, we show that plants with more chromosomes have more microsatellite bands and that isolation by distance plays a small role in shaping microsatellite diversity of P. alpina in the Swiss Alps.     

Isolation and characterization of microsatellite loci in the Caribbean sea fan coral, Gorgonia ventalina

Here we report primers for 10 microsatellite loci from the Caribbean sea fan coral, Gorgonia ventalina. Primers were tested on 237 genomic DNA extracts taken directly from tissue samples of G. ventalina. All loci were polymorphic with allelic richness ranging from 4 to 52. Expected heterozygosity ranged from 0.14 to 0.96. Preliminary data suggest that these microsatellites will be useful tools for studies of the population genetics of this important Caribbean coral species.     

Isolation and characterization of polymorphic microsatellite loci for the invasive plant Cytisus scoparius

Scotch broom (Cytisus scoparius) is a serious weed of natural and pastoral ecosystems and is invasive in many countries worldwide. Eight polymorphic microsatellite loci were developed and characterized for this species. The number of alleles per locus ranged from five to 23. The range of observed heterozygosity was between 0.207 and 0.928. These microsatellite markers will be useful tools for studies of population genetics in the native and invasive range of this species.     

Isolation and characterization of microsatellite loci in the invasive Alliaria petiolata (Brassicaceae)

Eight novel polymorphic microsatellite loci are presented for garlic mustard (Alliaria petiolata, Brassicaceae) a European herb that is a serious invader of North American deciduous forests. The microsatellites will be useful tools to analyse pathways of introduction of garlic mustard, as well as its evolutionary potential in the invasive range.     

Isolation and characterization of microsatellite loci in the entomopathogenic nematode Heterorhabditis bacteriophora

Twenty microsatellite loci were identified from genomic DNA enrichment and expressed sequence tags of entomopathogenic nematode Heterorhabditis bacteriophora. Eight loci were found to be polymorphic in a Northeast Ohio H. bacteriophora population. Levels of polymorphism were evaluated in 31-56 individuals and the number of alleles ranged from two to three. The values of observed and expected heterozygosities ranged from 0 to 0.536 and from 0.223 to 0.616, respectively. All eight loci showed heterozygote deficiencies, but three conformed to Hardy-Weinberg equilibrium at the subpopulation level. This is the first set of microsatellite markers in entomopathogenic nematodes.     

Isolation and characterization of microsatellite loci in Alasmidonta heterodon (Bivalvia: Unionidae)

We developed 13 species‐specific microsatellite markers for the federally endangered Atlantic slope unionid Alasmidonta heterodon. Four to 18 alleles per locus were observed among 30 individuals. Observed heterozygosity throughout the loci ranged from 26.9 to 86.2% and averaged 63.6%. Estimates of individual pairwise genetic distances indicated that levels of genetic diversity among loci were sufficient to produce unique multilocus genotypes for all animals surveyed. Randomization tests showed that genotypes for this collection were consistent with Hardy–Weinberg expectations, and no significant linkage disequilibrium was observed between loci. These loci therefore appear suitable for population surveys, kinship assessment and other such applications.     

Isolation and characterization of polymorphic microsatellite loci in white truffle (Tuber magnatum)

Tuber spp. are fungi that establish symbiosis with several trees and shrubs. Some of these fungal species produce edible ascomata, also known as truffles, which are highly appreciated for their taste and odour. We isolated and characterized eight polymorphic microsatellite loci from Tuber magnatum, the finest white truffle species, and assessed their variability in 370 individuals collected from all over the species range of distribution. Although two to 18 alleles per locus were found, no heterozygous individuals were observed. The availability of simple sequence repeat loci provides valuable tools for assessment of the genetic structure and population dynamics in this species.