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Understanding the genetic targets of natural selection is one of the most challenging goals of population genetics. Some of the earliest candidate genes were identified from associations between allozyme allele frequencies and environmental variation. One such example is the clinal polymorphism in the arginine kinase (Ak) gene in the marine snail Littorina fabalis. While other enzyme loci do not show differences in allozyme frequencies among populations, the Ak alleles are near differential fixation across repeated wave exposure gradients in Europe. Here, we use this case to illustrate how a new sequencing toolbox can be employed to characterize the genomic architecture associated with historical candidate genes. We found that the Ak alleles differ by nine nonsynonymous substitutions, which perfectly explain the different migration patterns of the allozymes during electrophoresis. Moreover, by exploring the genomic context of the Ak gene, we found that the three main Ak alleles are located on different arrangements of a putative chromosomal inversion that reaches near fixation at the opposing ends of two transects covering a wave exposure gradient. This shows Ak is part of a large (3/4 of the chromosome) genomic block of differentiation, in which Ak is unlikely to be the only target of divergent selection. Nevertheless, the nonsynonymous substitutions among Ak alleles and the complete association of one allele with one inversion arrangement suggest that the Ak gene is a strong candidate to contribute to the adaptive significance of the inversion. [ABSTRACT FROM AUTHOR]

Quinolin-8-yl 3-(4,4-difluoropiperidine-1-sulfonyl)-4-methylbenzoate (2F-QMPSB) and 3-(4,4-difluoropiperidine-1-sulfonyl)-4-methyl- N -(2-phenylpropan-2-yl)benzamide (SGT-233) belong to a new group of synthetic cannabinoid receptor agonists containing a sulfamoyl benzoate or sulfamoyl benzamide core structure. 2F-QMPSB was identified in herbal material seized in Europe in 2018. The aims of this study were the identification of in vitro Phase I and II metabolites of 2F-QMPSB and SGT-233 to find analytical targets for toxicological screenings. Furthermore, the contribution of different monooxygenases and human carboxylesterases to Phase I metabolism was investigated. Liquid chromatography coupled to high-resolution tandem mass spectrometry was used for analysis. Ester hydrolysis was found to be an important step in the metabolism of 2F-QMPSB, which was catalyzed mainly by human carboxylesterases (hCES)1 isoforms. Additionally, nonenzymatic ester hydrolysis was observed in case of 2F-QMPSB. Notably, the carboxylic acid product derived from ester hydrolysis and metabolites thereof were only detectable in negative ionization mode. In case of SGT-233, mono- and dihydroxy metabolites were identified, as well as glucuronides. The cytochrome P450 (CYP) isozymes CYP2C8, CYP2C9, CYP2C19, CYP3A4 and CYP3A5 were found to be involved in the hydroxylation of both compounds. The results of these in vitro experiments suggest that the ester hydrolysis products of 2F-QMPSB and their glucuronides are suitable targets for toxicological screenings. In the case of SGT-233, the mono- and dihydroxy metabolites were identified as suitable screening targets. The involvement of various CYP isoforms in the metabolism of both substances reduces the likelihood of drug–drug interactions due to CYP inhibition. [ABSTRACT FROM AUTHOR]

The European hake Merluccius merluccius is one of the most commercially important and widely distributed fish species, occurring both in European and Mediterranean Sea fisheries. We analyzed the distribution and infection rates of different species of Anisakis in M. merluccius (N = 1130 hakes), by site of infection in the fish host (viscera, dorsal and ventral fillets) from 13 different fishing grounds of the Mediterranean Sea (FAO area 37). The fillets were examined using the UV-Press method. A large number of Anisakis specimens (N = 877) were identified by diagnostic allozymes, sequence analysis of the partial EF1 α-1 region of nDNA and mtDNA cox2 gene. Among these, 813 larvae corresponded to A. pegreffii, 62 to A. physeteris, 1 to A. simplex (s. s.), whereas one resulted as a F1 hybrid between A. pegreffii and A. simplex (s. s.). Remarkably high levels of infection with A. pegreffii were recorded in hakes from the Adriatic/Ionian Sea compared to the fish of similar length obtained from the western Mediterranean fishing grounds. A positive correlation between fish length and abundance of A. pegreffii was observed. Concerning the localization of A. pegreffii larvae in the fish, 28.3% were detected in the liver, 62.9% in the rest of the viscera, 6.6% in the ventral part of the flesh, whereas 2.1% in the dorsal flesh. [ABSTRACT FROM AUTHOR]

The root-knot nematode Meloidogyne ulmi is synonymised with Meloidogyne mali based on morphological and morphometric similarities, common hosts, as well as biochemical similarities at both protein and DNA levels. M. mali was first described in Japan on Malus prunifolia Borkh.; and M. ulmi in Italy on Ulmus chenmoui W.C. Cheng. Morphological and morphometric studies of their holo- and paratypes revealed important similarities in the major characters as well as some general variability in a few others. Host test also showed that besides the two species being able to parasitize the type hosts of the other, they share some other common hosts. Our study of the esterase and malate dehydrogenase isozyme phenotypes of some M. ulmi populations gave a perfectly comparable result to that already known for M. mali. Finally, phylogenetic studies of their SSU and LSU rDNA sequence data revealed that the two are not distinguishable at DNA level. All these put together, leave strong evidences to support the fact that M. ulmi is not a valid species, but a junior synonym of M. mali. Brief discussion on the biology and life cycle of M. mali is given. An overview of all known hosts and the possible distribution of M. mali in Europe are also presented. [ABSTRACT FROM AUTHOR]

The perennial herbs Silene vulgaris and S. uniflora are closely related, partially sympatric and interfertile, yet morphologically distinct. We used nuclear (allozyme) and plastid (polymerase chain reaction-restriction fragment length polymorphism) DNA markers to investigate whether these species have a shared history of postglacial colonization and hybridization in Europe, as inferred from large-scale patterns of geographic variation. The majority of plastid haplotypes and allozyme alleles were widespread and patchily distributed within both species and there was no geographic structure in the distributions of shared allozymes or haplotypes. The mosaic variation is consistent with a scenario in which repeated episodes of interspecific hybridization pre-dated the largely allopatric range expansion of the two species during the postglacial period. Our overall results are not consistent with a scenario of extensive hybridization and introgression during the postglacial range expansion of the species or within their current areas of sympatry, but we found some evidence for local, postglacial evolution and hybridization in the Baltic region. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, , 127-148. [ABSTRACT FROM AUTHOR]

Information from allozymes, ploidy levels, morphology, cross-compatibility and biogeography suggests that the easternmost occurrences of the Ponto-Caucasian Viola sieheana should be considered to belong to a separate species, V. caspia. Morphological characters delimitating V. sieheana and V. caspia are presented and discussed. The main distribution of V. sieheana s. str. is in the eastern Balkans, Turkey, Cyprus, and The Lebanon, and of V. caspia in the Caspio-Caucasian region westwards to Crimea and north-eastern Turkey. Their distributions in the intermediate areas remain unknown. Plants of V. sieheana s. str. from Cyprus, Greece, and Turkey were all blue-flowered and had the chromosome number 2 n = 12 x = 60. Its presence in the Peloponnese (Parnon, Taÿgetos, Menalon) and in the Pindhos mountains, Greece, was confirmed. Reports of plants with 2 n = 8 x = 40 from these stations seem to refer to the sterile hybrid V. reichenbachiana × sieheana which is locally abundant. V. caspia from Azerbaijan had 2 n = 8 x = 40 and had either whitish or blue flowers. In spite of sympatry and almost complete cross-compatibility, the two corolla colour morphs showed strong allozymic differentiation in four out of seven isozyme systems, suggesting reproductive isolation and incipient speciation. Within section Viola, V. caspia and V. sieheana seem no more closely related to each other than to either of the other investigated European species. The possibility that V. sieheana is an ancient allopolyploid involving the Greek narrow endemic V. dirphya (2 n = 40) is discussed. [ABSTRACT FROM AUTHOR]

The article focuses on a study that applied allozyme electrophoresis to examine the distribution of genetic variation within and among mainland and insular populations of the lacertid lizard Podarcis (P.) muralis from western, southern and eastern Europe. The researchers found that the highest values of percent polymorphism and heterozygosity were in the samples from two Tyrrhenian islands, which they attribute to the populations' marginal environments that were characterized by temporal-ecological instability. The results of their genetic heterogeneity analysis are said to indicate a certain amount of genetic differentiation among local populations of P. muralis.

The aim of this study was to estimate genetic diversity and assess its importance for plant fitness in a species belonging to the most endangered species in Europe, Dracocephalum austriacum L., and to select the most valuable populations for conservation of genetic diversity within the species in the studied regions. We analyzed allozyme variation of 12 populations in three distinct regions (Czech Karst, Moravia and Slovak Karst) in Central Europe. The results showed high genetic diversity within populations (80.14%) and relatively low differentiation among populations within regions (9.42%) and between regions (10.45%). Seed production was significantly higher in larger, genetically more diverse and less inbred populations. The results suggest that genetic diversity has important effect on seed production in this species and thus can be expected to have strong direct consequences for plant fitness and vitality of the whole populations. They also show large variation in genetic diversity between populations and indicate which populations should get a priority in attempts to conserve all the genetic diversity within the region. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus traditionally has been characterized by insulin resistance and β-cell dysfunction, leading to hyperglycemia and eventual micro- and macrovascular complications. Dipeptidyl peptidase-4 (DPP-4) inhibitors are a relatively new class of drugs available for the management of type 2 diabetes. In order to provide a comprehensive evaluation and comparison of the pharmacology, pharmacokinetics, efficacy, and safety of the DPP-4 inhibitors--sitagliptin, vildagliptin, saxagliptin, and alogliptin--in the treatment of type 2 diabetes, we conducted a MEDLINE search (1966-July 2009) for pertinent English-language articles. Abstracts of the annual meetings of the American Diabetes Association and European Association lot the Study of Diabetes from 2005-2009 were also searched. As a drug class, the DPP-4 inhibitors have become widely accepted in clinical practice because of their low risk of hypoglycemia, favorable adverse-effect profile, and once-daily dosing. They are weight neutral (do not cause weight gain or loss) and appear to decrease β-cell apoptosis and increase β-cell survival. Because clinical studies directly comparing agents from this class have not, to our knowledge, been conducted, making comparisons in terms of efficacy and safety will become difficult for clinicians as more agents become available. Based on information front preclinical, clinical, and postmarketing data, there does not appear to be a compelling advantage of one DPP-4 inhibitor over another in terms of efficacy, safety, or ease of clinical use. Although theoretical advantages exist for agents with a higher specificity for DPP-4 inhibition versus inhibition of other isoenzymes associated with toxicity, comparative studies and/or increased clinical experience with this class of drug will determine the clinical advantages, if any, of one agent over another. [ABSTRACT FROM AUTHOR]

Pairwise sequence polymorphism in mitochondrial DNA and levels of differentiation among presumptive gene loci (expressed as Nei's D) tend to be greater between populations separated by the Strait of Gibraltar than between populations inhabiting either Morocco or Spain. Ancestral Psammodromus algirus inhabiting Iberia and North Africa while the Strait of Gibraltar was being formed and stabilized (Miocene-Pliocene) evolved in association with physiogeographic change brought about by this barrier to gene exchange. Considered in units of genetic change per kilometer, mtDNA differentiation is greater in Morocco than in Spain, and allozyme differentiation is slightly greater than, or equal to, that in Spain, suggesting that P. algirus has a longer and more complex history in Morocco than in Spain. [ABSTRACT FROM AUTHOR]

Background: The prevalence and causes of anemia among patients with Fabry disease are unknown.Methods: In a cross-sectional study we examined hemoglobin concentrations of patients with Fabry disease using a large international database, the Fabry Outcome Survey (FOS), and analyzed the association of renal function, heart failure, gastrointestinal symptoms, and inflammation, with anemia (hemoglobin <12 g/dL in females and <13 g/dL in males).Results: Anemia was present in 34% of 345 patients with Fabry disease. Median hemoglobin in 158 females was 12.9 g/dL and the median hemoglobin of 187 male patients was 13.2 g/dL. The prevalence of anemia among females was 20%, and among males 47%. Among patients with normal renal function [estimated glomerular filtration rate (GFR) >90 mL/min/1.73 m(2)] and anemia, heart failure [New York Heart Association (NYHA) class II to IV] and/or elevated C-reactive protein (CRP) levels were documented in 82% of patients. Up to 67% of patients with decreased estimated GFR presented with anemia. There was also a trend for lower hemoglobin levels among patients with signs of inflammation (defined by an elevated CRP level). We observed no association of the presence of gastrointestinal symptoms with anemia. Analyses in 53 patients receiving enzyme replacement therapy for up to 2 years, suggest no effect on anemia.Conclusion: The results of this study point to a high prevalence of anemia among patients with Fabry disease that is in most instances related to impaired renal function, heart failure, and inflammation. This finding may be of clinical relevance, because anemia is a major risk factor for patients with kidney disease, heart failure, or stroke, which are important manifestations of Fabry disease. [ABSTRACT FROM AUTHOR]

Carapelli, A., Frati, F., Fanciulli, P. P., Nardi, F.&Dallai, R. (2005). Assessing species boundaries and evolutionary relationships in a group of south-western European species ofIsotomurus(Collembola, Isotomidae) using allozyme data.— Zoologica Scripta,34, 71–79.In this study allozyme data were used to examine evolutionary relationships in the cosmopolitan collembolan genusIsotomurus. Fifty-six south-western European populations from 13 species were compared, with the aim of delimiting species boundaries and testing the robustness of the most frequently used morphological characters for species identification. Observed allozyme variability suggests that genetic differentiation is more pronounced than the amount of morphological variability among and within species. Convergence in models of pigmentation pattern may lead to erroneous taxonomic identification when this is the only feature used for species diagnosis. In this respect, this study confirms that diagnosis is greatly improved when assisted by biochemical or molecular analyses. Allozyme data have also been used to reconstruct evolutionary hypotheses for relationships at the species and population level. The monophyly ofIsotomurus maculatus,I. unifasciatus,I. fucicolus,I. nebulosusandI. pseudopalustriswas confirmed on molecular grounds. Conversely, the monophyly ofI. ghibellinusandI. palustriswas rejected, suggesting the presence of cryptic species. [ABSTRACT FROM AUTHOR]

The phylogeography of ‘southern’ species is relatively well studied in Europe. However, there are few data about ‘northern’ species, and so we studied the population genetic structure of the arctic-alpine distributed burnet moth Zygaena exulans as an exemplar. The allozymes of 209 individuals from seven populations (two from the Pyrenees, five from the Alps) were studied by electrophoresis. All 15 analysed loci were polymorphic. The mean genetic diversities were moderately high ( A: 1.99; He: 11.5; P: 65%). Mean genetic diversities were significantly higher in the Alps than in the Pyrenees in all cases. FST was 5.4% and FIS was 10%. Genetic distances were generally low with a mean of 0.022 between large populations. About 62% of the variance between populations was between the Alps and the Pyrenees. The two samples from the Pyrenees had no significant differentiation, whereas significant differentiation was detected between the populations from the Alps ( FST = 2.8%, P = 0.02). Zygaena exulans had a continuous distribution between the Alps and the Pyrenees during the last ice age. Most probably, the species was not present in Iberia, and the samples from the Pyrenees are derived from the southern edge of the glacial distribution area and thus became genetically impoverished. Post-glacial isolation in Alps and Pyrenees has resulted in a weak genetic differentiation between these two disjunct high mountain systems. [ABSTRACT FROM AUTHOR]

The systematic structure and postglacial population history of the freshwater amphipod Gammarus lacustris were explored in an allozyme survey of 65 populations across Northern Europe. A strong multilocus pattern of differentiation discriminated populations of the north-east (north-eastern Norway, northern Finland) from those in the west and the south (southern and central Scandinavia, Denmark, Poland). This principal division is attributed to postglacial colonization of the area by two main refugial races or lineages, one from the east (Russia), the other from the south (north-western European continent). The strongly diverged Eastern and Western races (Nei's D = 0.3, from 22 loci) now meet in a secondary contact zone across a narrow sector of northernmost Norway. Genetic population compositions in this zone vary in a mosaic pattern, and show no evidence of reproductive incompatibility. Similar contacts of eastern and western lineages, far older than the latest glaciation, are now known from a number of taxa and they constitute a general pattern in Fennoscandian phylogeography. Within the Western Gammarus race, the populations through coastal north-western Norway are further distinguished from those in southern Scandinavia and Denmark by a set of unique alleles at high frequencies (D = 0.12). This suggests an independent early colonization of the coastal region by another distinct stock, either along an early deglaciated coastal corridor from the south-west, or directly from the ice-free continental shelf off the Norwegian coast – a hypothesis that has also previously been presented for G. lacustris , and parallels controversial suggestions of local refugia for other taxa in Scandinavia. The coastal population type only later could come into contact with Gammarus invading over the mountains from the south; these two population types now smoothly intergrade. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79,... [ABSTRACT FROM AUTHOR]

Compares, on the basis of allozyme polymorphism data, genetic variability and differentiation between core, peripheral and isolated populations of the scarce heath, a butterfly endangered in Northern and Central Europe. Conclusions, including that isolation in combination with marginality have caused an erosion of the gene pool and that the observed patterns may be caused both by the contemporary population structure of the species, as well as by the colonisation history.

F-statistics were employed to analyze quantitative and allozyme variation among 19 native populations of maritime pine (Pinus pinaster Alt.) Fourteen polymorphic allozyme loci were used to provide an empirical basis for constructing a null hypothesis to test natural selection as a determinant of quantitative evolution in stem form, total height growth and survival at 30 years old. Hidden biases, that may result in a difference between quantitative (Q[subST]) and allozyme (F[subST]) differentiation which are not because of the action of natural selection, were avoided by comparing pairs f populations using linear models. All quantitative traits showed higher differentiation than allozymes. The highest divergence was found in stem form, whereas divergences in total height and survival were significantly lower. Differential adaptation to regional and local patterns of precipitation, temperature and soil type seem to be the best explanation of the different structure found in quantitative traits and allozyme loci. Possible bias in the estimation of Q[subST] due t the level of quantitative within-population diversity and the role of adaptation of maritime pine after the last glaciation to highly diverse ecological conditions are discussed with special reference to the actual geographical structure of gene diversity in the species; native range. [ABSTRACT FROM AUTHOR]

Genetic diversity within a common bean (Phaseolus vulgaris L.) collection, comprising 343 accessions from the Iberian Peninsula, was examined using six allozyme markers. Two major clusters corresponding to the Andean and Mesoamerican gene pools were identified. Both gene pools were characterized by specific alleles, with the former exhibiting Skdh100, Me100, Rbcs100 or 98 and Diap-1100, and the latter exhibiting Skdh103, Me100, Rbcs100 and Diap-195. Some accessions from both clusters, deviating from these allozyme patterns, exhibited Skdh100, Me100, Rbcs100 and Diap-195 or Skdh103, Me100, Rbcs100 and Diap-1100 allozyme profiles and were considered as putative hybrids.The levels of genetic variation has not been eroded since the introduction of the common bean from the American centers of domestication to the Iberian Peninsula. Instead, obvious signs of introgression between the two gene pools were observed, mainly among white-seeded genotypes. The intermediate forms adapted to the Iberian Peninsula could have emerged from initial recombination between Mesoamerican and Andean gene pools. The Iberian common bean germplasm is therefore more complex than previously thought, and contains additional diversity that remains to be explored for genetic and breeding purposes. The Iberian Peninsula could be considered as a secondary center of genetic diversity of the common bean, especially the large white-seeded genotypes. [ABSTRACT FROM AUTHOR]

Objective: To determine the isotypes and clonality of antibodies to GAD (GADA) and IA-2 (IA-2A) in patients with type 1 and type 2 diabetes.Research Design and Methods: We studied the following consecutive series of patients who attended a diabetes center for antibodies to GADA and IA-2A: 52 newly diagnosed type 1 diabetic patients, 199 type 2 diabetic patients, 200 control patients, and a cohort of 34 nondiabetic identical twins of patients with type 1 diabetes (15 of whom developed diabetes) who were followed prospectively.Results: GADA or IA-2A were detected in 37 (71%) type 1 diabetic patients compared with only 10 (5%) type 2 diabetic patients (P<0.0001). Both GAD and IA-2 antibodies, regardless of the type of diabetes, were usually subclass restricted to IgG1 and were polyclonal. IgM, IgG3, and IgE isotypes were also detected, but all isotypes of GADA and IA-2A were less prevalent than IgG1 (P<0.017 for either antibody). There was no evidence of spreading or switching of isotypes before the onset of type 1 diabetes.Conclusions: These observations suggest that the pathogenesis of antigen-specific antibodies in type 1 and type 2 diabetes is similar and probably involves a chronic nonrandom antigen-driven polyclonal B-cell activation that is consistent with a Th1-type immune response. [ABSTRACT FROM AUTHOR]

We investigated the genetic population structure in a metapopulation of the plant Silene latifolia (Caryophyllaceae) and its fungal pathogen Microbotryum violaceum (Ustilaginales), a pollinator-borne disease. Population structure of the host plant was estimated using allozyme markers and that of the fungus by microsatellites. Both host and parasite showed significant differentiation, but parasite populations were 12 times more strongly differentiated than those of the hosts. We found significant isolation by distance for host populations but not for parasite populations. Higher population differentiation for the parasite may result from small effective population size, high selfing rates, or low migration rate. In this system, hosts are obligate outcrossers and they migrate by seeds and pollen, whereas parasites can self-fertilize and migrate only on pollinating insects. We discuss the effect of limited gene flow in this parasite on its coevolutionary interaction with its host, and its potential for local adaptation on sympatric host populations. [ABSTRACT FROM AUTHOR]

Compatible data from 11 polymorphic allozyme loci were assembled from 14 published studies and additional unpublished information for 232 native collections of brown trout sampled over a broad geographical range. Most of the genetic variation was explained by the distribution of allelic variation at the LDH-C* and CK-A1* loci. Patterns of geographical distribution coupled with postglacial geological events supported a model of colonization from three preglacial lineages, each fixed for different sets of alleles at these two loci. During glacial retreat, recolonization is proposed to have occurred mainly into adjacent areas through (i) a north-western migration from an eastern Mediterranean–Caspian refuge, (ii) a northern expansion from a refuge in Atlantic drainages of Iberia and southern France, and (iii) a northern and eastern radiation from a refuge centred near the English Channel. Extant populations in deglaciated areas are suggested to represent mixed or pure descendants of these migrating groups. Repopulation from a fourth Mediterranean refuge distinguished by the presence of the LDH-A2*100QL allele was excluded based on the absence of this allele in repopulated areas. [ABSTRACT FROM AUTHOR]

Clonal material of the temperate C4 species Cyperus longus L. (Cyperaceae) sampled from Cornwall, S. W. Great Britain and Mt Pilion, central Greece was grown under the same environmental conditions. Comparisons were made of the pattern of leaf growth, net photosynthesis (Pn) and the characteristics of the isoenzymes of glutamine synthetase (GS). In addition, we studied the morphological characteristics of these clones and 95 herbarium specimens collected from a range of localities throughout Europe. Principal-components analysis of the morphological characteristics suggested that European material falls into two distinct morphological groups, typical C. longus and ssp. badius (Desf.) Murb. The clonal material from Cornwall corresponded morphologically with ssp. fungus and that from Mt Pilion with ssp. badius. Physiological and biochemical measurements of the two clones indicated distinct differences in the phenology, Pn and stomatal conductance at high light levels, their complements of GS1 and GS2 isoforms and associated temperature stability. It appears, therefore, that ssp. badius represents a distinct ecotype of ssp. longus. However, the apparent taxonomic distinction between the groups requires further investigation of population variation, as our studies were performed on a limited amount of clonal material. [ABSTRACT FROM AUTHOR]

Apera spica-venti L., a widely distributed weed in Europe, has recently become established as a weed of winter cereals in Canada. Levels of genetic variation were compared between and within nine Canadian and six native European populations grown under uniform conditions. Both the Canadian and European populations showed high levels of variation among populations with respect to 31 life history and morphological traits. As one would have predicted, greater differences were recorded among the European populations, although only one population in each group was clearly distinct from the other populations. High levels of genetic variability in allozyme characters were also evident in both the Canadian and European populations (percentage of polymorphic loci = 57 to 62 %, number of alleles per locus = 2.53 and levels of heterozygosity = 0.23). There was, however, little or no divergence in allozyme characters among populations, with all populations having very high genetic identity values (0.948 to 0.998) and only 1.0 to 2.4 % of the total gene diversity allocated to the among-population component. The extent of within-population variation in the 31 life-history and morphological characters were similar in both introduced and native populations. Studies of population structure in three Canadian populations indicated that most of the variation in nine morphological characters occurred among progeny within families rather than among families. Estimates of outcrossing rate (t) using allozyme markers at two loci equalled 1.0, indicating random mating. Selfing experiments indicated that the plants were predominantly self-incompatible. The amounts and patterns of genetic variation are consistent with what one would expect in an outcrossing species and do not support the hypothesis of genetically depauperate introductions. [ABSTRACT FROM AUTHOR]

The spatial distribution of alleles is described in a forest stand of natural origin of 5 ha comprising 355 mature Quercus petraea and Q. robur trees. Each tree was genotyped for six microsatellite loci. Previous studies on the same population based on isozymes allowed a comparison of different markers for the detection of spatial genetic structure. Different statistics were used: differentiation measures at different spatial scales, and spatial autocorrelation analysis based on Moran’s index I. For microsatellites, differentiation and autocorrelation were calculated with unordered alleles (identity in state) and with alleles ordered according to their size. Results showed the same tendency of a significant, but low, spatial genetic structure for markers and different statistics. Some differences could, however, be detected. First, microsatellites interpreted as unordered alleles exhibit stronger spatial structure than isozymes or microsatellite interpreted as ordered alleles. Second, differentiation and autocorrelation values were higher in Q. petraea than in Q. robur. These differences were attributed to species differences in gene flow via pollen or seed. [ABSTRACT FROM AUTHOR]

The European ‘sand-goby‘ genera, comprising the Atlantic-Mediterranean Pomatoschistus and Gobiusculus, Ponto-Caspian Knipowitschia and West Balkanian Economidichthys, are diagnosed, with special reference to patterns of infraorbital neuromast organs (sensory papillae) A survey of selected meristic features indicates synapomorphies in increased number of abdominal and caudal vertebrae, and additional interneural spaces between first and second dorsal fin pterygiophores. Absence of a crest-like postmaxillary process on the premaxilla was found to be another derived feature after a survey of this bone throughout the Gobioidei. Affinity with other Atlantic-Mediterranean genera (Deltentosteus, Buenia, Lebetus and, probably, Speleogobius) is established from both morphological and isozyme criteria. Using head lateral-line and meristic characters, as well as occurrence of the premaxilla crest, a search for a sister group has led to the Indo-Pacific Nesogobius, a genus endemic to southern Australian seas, and probable wider relationship to North-western Pacific endemic gobiids. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the population structure of Atlantic salmon (Salmo salar L.) throughout the species range would help to determine the impact that cultured fish could have on wild populations. To help achieve this aim, Atlantic salmon samples were obtained from 14 locations throughout Europe (including Iceland) and screened for variation at 32 allozyme loci. A sample was also obtained from Canada to serve as an out-group. Seventeen allozyme loci were found to be variable in one or more of the populations studied and three, sAAT-4*, IDDH-2*, and mMEP-2* were variable across the range. This is the widest-ranging study to include ESTD-2*, FBALD-3*, and TPI-3*, which combined contributed 28% to the total genetic diversity detected. Genotype frequencies complied with Hardy-Weinberg expected proportions. Over all loci, highly significant heterogeneity was observed between samples. Alternate alleles segregating at ESTD-2* were found to be largely exclusive to Europe or North America. A neighbour-joining dendrogram was constructed to visualize relationships between populations and was consistent with previous findings that revealed Baltic and European clusters, with the Canadian population being the most genetically distinct. A significant association was observed between geographic and genetic distance, which suggests the potential for local adaptation, thus highlighting the need for conservation of wild populations. [ABSTRACT FROM PUBLISHER]

Morphological markers and isozymes were used for identifying three presumed species of the Isotoma genus. Morphological traits separated three taxa of the genus. 10 isozymes determined by at least 11 loci were analysed from each taxon, and 2 loci were taxon-specific, supporting the hypothesis that the three taxa represented three species. The genetic variation found within the taxa measured as fraction of polymorphic loci at the 99% level was 0.82, 0.55 and 0.55 with the corresponding observed heterozygosity 0.15, 0.09 and 0.12. Two populations of the same taxon from Denmark and Norway, respectively, were very closely related. Additional ecological criteria, obtained from a literature survey, also revealed pronounced differences between the three taxa. Due to these facts three distinct species are proposed, namely I. anglicana Lubbock 1862, I. riparia Nicolet 1841 and I. viridis Bourlet 1839. [ABSTRACT FROM AUTHOR]

Southwestern Europe has been considered as a secondary centre of genetic diversity for the common bean. The dispersal of domesticated materials from their centres of origin provides an experimental system that reveals how human selection during cultivation and adaptation to novel environments affects the genetic composition. In this paper, our goal was to elucidate how distinct events could modify the structure and level of genetic diversity in the common bean. The genome-wide genetic composition was analysed at 42 microsatellite loci in individuals of 22 landraces of domesticated common bean from the Mesoamerican gene pool. The accessions were also characterised for phaseolin seed protein and for nine allozyme polymorphisms and phenotypic traits. One of this study's important findings was the complementary information obtained from all the polymorphisms examined. Most of the markers found to be potentially under the influence of selection were located in the proximity of previously mapped genes and quantitative trait loci (QTLs) related to important agronomic traits, which indicates that population genomics approaches are very efficient in detecting QTLs. As it was revealed by outlier simple sequence repeats, loci analysis with STRUCTURE software and multivariate analysis of phenotypic data, the landraces were grouped into three clusters according to seed size and shape, vegetative growth habit and genetic resistance. A total of 151 alleles were detected with an average of 4 alleles per locus and an average polymorphism information content of 0.31. Using a model-based approach, on the basis of neutral markers implemented in the software STRUCTURE, three clusters were inferred, which were in good agreement with multivariate analysis. Geographic and genetic distances were congruent with the exception of a few putative hybrids identified in this study, suggesting a predominant effect of isolation by distance. Genomic scans using both markers linked to genes affected by selection (outlier) and neutral markers showed advantages relative to other approaches, since they help to create a more complete picture of how adaptation to environmental conditions has sculpted the common bean genomes in southern Europe. The use of outlier loci also gives a clue about what selective forces gave rise to the actual phenotypes of the analysed landraces.

In this paper, we present results of the first comprehensive study of the introgression of both autosomal and sex-chromosome markers across the central European portion of the hybrid zone between two house mouse subspecies, Mus musculus musculus and M. m. domesticus. More than 1800 individuals sampled from 105 sites were analyzed with a set of allozyme loci (hopefully representing neutral or nearly neutral markers) and X-linked loci (which are assumed to be under selection). The zone center is best modeled as a single straight line independent of fine-scale local geographic or climatic conditions, being maintained by a balance between dispersal and selection against hybrids. The width (w) of the multilocus autosomal cline was estimated as 9.6 km whereas the estimate for the compound X-chromosome cline was about 4.6 km only. As the former estimate is comparable to that of the Danish portion of the zone (assumed to be much younger than the central European one), zone width does not appear to be related to its age. The strength (B) of the central barrier was estimated as about 20 km; with dispersal (sigma) of about 1 km/gen(1/2), this means effective selection (s*) is approximately 0.06-0.09 for autosomal loci and about 0.25 for X-linked loci. The number of loci under selection was estimated as N= 56-99 for autosomes and about 380 for X-linked loci. Finally, we highlight some potential pitfalls in hybrid zone analyses and in comparisons of different transects. We suggest that conclusions about parts of the mouse genome involved in reproductive isolation and speciation should be drawn with caution and that analytical approaches always providing some estimates should not be used without due care regarding the support or confidence of such estimates, especially if conclusions are based on the difference between these estimates. Finally, we recommend that analysis in two-dimensional space, dense sampling, and rigorous treatment of data, including inspection of likelihood profiles, are essential for hybrid zone studies.

The brittle-star Acrocnida brachiata (Montagu) lives in sandy-bottom habitat of both intertidal and subtidal zones along the coasts of the northwestern Europe. An allozyme frequency-based survey (five enzyme loci) was combined with a mitochondrial (mt) COI haplotype analysis (598-bp sequences) on 17 populations to trace back past colonization pathways from the actual population structure of the species. Both genetic markers display a sharp genetic break between intertidal (clade I) and subtidal populations (clade S). This break corresponds to an allele frequency inversion at three enzyme loci (Hk, Pgm and Pgi) and a deep divergence of about 20% in mtCOI sequences between most of the intertidal populations and other samples. The geographic distribution of clade I seems to be more restricted than clade S as it is absent from the intertidal of the eastern English Channel and North Sea and may be replaced by clade S in south Brittany. Applying previously published rates of mutation, divergence between the two clades is estimated to pre-date 5 million years ago and may be due to allopatric speciation processes at the Mio-Pliocene transition. The occurrence of putative hybrids in a few localities, however, suggests incomplete cryptic speciation with secondary contact zones. The relative importance of colonization history vs. habitat specialization are discussed in the light of neutral evolution as tested from mtCOI gene sequences. While differential selection seems to have contributed little to the separation of the lineages, it may have played a role in the emergence of adaptive polymorphisms in the hybrid zone. Furthermore, congruent spatial patterns of differentiation were observed in both clades suggesting a recent increase in population size. These findings are in agreement with a recent expansion of the populations during or after the formation of the English Channel, from a southern refuge for the subtidal clade whereas the intertidal clade may have persisted further north. As previously suspected for a species with a very short pelagic larval phase, contemporary gene flow between distant or adjacent populations appears to be extremely reduced or even absent.

Over several decades, the distribution patterns and evolution of alpine disjunct species has become an increasingly discussed subject. Large scale genetic analysis has allowed the resolution of the past range changes and intraspecific evolution of many species, in Europe especially of Mediterranean origin. However, the phylogeographic structures of species with arctic-alpine disjunct distribution patterns are relatively poorly studied. The existing phylogeographic analysis (mostly of alpine plant species) supports disjunct distributions during glacial as well as post-glacial periods for a number of species. However, several questions still remain unresolved and we therefore analysed the Mountain Ringlet Erebia epiphron as a model for such alpine disjunct species. We found strong differentiation into five different lineages supporting five differentiation centres: (i) the eastern Pyrenees, (ii) the mountain ranges between the central Pyrenees and south-western Alps, (iii, iv) two areas along the southern Alps margin and (v) the northern Alps margin. We propose that these patterns evolved due to the humidity requirements of this species, which did not allow survival in the dry glacial steppes, but along the margins of the wetter glaciated high mountain ranges.

A collection of 148 Pisum accessions, mostly from Western Europe, and including both primitive germplasm and cultivated types, was structured using 121 protein- and PCR-based markers. This molecular marker-based classification allowed us to trace back major lineages of pea breeding in Western Europe over the last decades, and to follow the main breeding objectives: increase of seed weight, introduction of the afila foliage type and white flowers, and improvement of frost tolerance for winter-sown peas. The classification was largely consistent with the available pedigree data, and clearly resolved the different main varietal types according to their end-uses (fodder, food and feed peas) from exotic types and wild forms. Fodder types were further separated into two sub-groups. Feed peas, corresponding to either spring-sown or winter-sown types, were also separated, with two apparently different gene pools for winter-sown peas. The garden pea group was the most difficult to structure, probably due to a continuum in breeding of feed peas from garden types. The classification also stressed the paradox between the narrowness of the genetic basis of recent cultivars and the very large diversity available within P. sativum. A sub-collection of 43 accessions representing 96% of the whole allelic variability is proposed as a starting point for the construction of a core collection.

Populus nigra L. is a pioneer tree species of riparian ecosystems that is threatened with extinction because of the loss of its natural habitat. To evaluate the existing genetic diversity of P. nigra within ex-situ collections, we analyzed 675 P. nigra L. accessions from nine European gene banks with three amplified fragment length polymorphism (AFLP) and five microsatellite [or simple sequence repeat (SSR)] primer combinations, and 11 isozyme systems. With isozyme analysis, hybrids could be detected, and only 3% were found in the gene bank collection. AFLP and SSR analyses revealed effectively that 26% of the accessions were duplicated and that the level of clonal duplication varied from 0% in the French gene bank collection up to 78% in the Belgian gene bank collection. SSR analysis was preferred because AFLP was technically more demanding and more prone to scoring errors. To assess the genetic diversity, we grouped material from the gene banks according to topography of the location from which the accessions were originally collected (river system or regions separated by mountains). Genetic diversity was expressed in terms of the following parameters: percentage of polymorphic loci, observed and effective number of alleles, and Nei's expected heterozygosity or gene diversity (for AFLP). Genetic diversity varied from region to region and depended, to some extent, on the marker system used. The most unique alleles were identified in the Danube region (Austria), the Rhône region (France), Italy, the Rijn region (The Netherlands), and the Ebro region (Spain). In general, the diversity was largest in the material collected from the regions in Southern Europe. Dendrograms and principal component analysis resulted in a clustering according to topography. Material from the same river systems, but from different countries, clustered together. The genetic differentiation among the regions (F(st)/G(st)) was moderate.

Recent decreases in biodiversity in Europe are commonly thought to be due to land use and climate change. However, the genetic diversity of populations is also seen as one essential factor for their fitness. Genetic diversity in species across the continent of Europe has been recognized as being in part a consequence of ice age isolation in southern refugia and postglacial colonization northwards, and these phylogeographical patterns may themselves affect the adaptability of populations. Recent work on butterfly species with different refugia, colonization paths and genetic structures allows this idea to be examined. The 'chalk-hill blue' pattern is one of decreasing genetic diversity from south to north, whereas the 'woodland ringlet' pattern shows greater genetic diversity in eastern than in western lineages. Comparison of population demographic trends in species with these biogeographical patterns reveals higher rates of decrease with lower genetic diversity. This indicates reduced adaptability due to genetic impoverishment as a result of glacial and postglacial range changes. Analysis of phylogeographical pattern may be a useful guide to interpreting demographic trends and in conservation planning.

Restriction fragment length polymorphism in the NAT1 gene was assayed to reveal 7 mutations (97C>T; 190C>T; 350,351G>C; 402T>C; 752A>T; D(1105); D(1025)) in 74 Europeans from West Siberia. New methods for detecting mutations 350,351G>C, 402T>C, 752A>T, D(1105), and D(1025) were proposed.

An earlier study of the morphological variation in the circumpolar genus Dryas in Greenland revealed that populations in east Greenland are highly variable and this variation was interpreted as a hybrid zone between D. octopetala and D. integrifolia. It was proposed that populations of Dryas in east Greenland immigrated postglacially from Svalbard. The purpose of our study was to investigate the population structure of the Dryas integrifolia-octopetala complex using a combination of morphological and genetic characters. Populations of Dryas were sampled in Greenland, Svalbard, Iceland and north Scandinavia (Sweden). The morphological traits clearly separated west Greenland from Svalbard, Iceland and north Scandinavia. A large number of individuals from east Greenland and some from north Greenland could be interpreted as hybrids between the morphs. The genetic pattern was, however, partly different as the greatest amount of differentiation among regions was found between west and north Greenland (FRT = 0.65). The highest degree of genetic variation appeared within east Greenland. This was in accordance with the putative hybrid origin of the populations, as concluded based on the morphological results. The total amount of genetic differentiation found among the six regions (FRT = 0.61) was larger than between the two species (FRT = 0.44). The genetic pattern matched the proposed postglacial migration routes.

The two expressed genes coding for N-acetyltransferase (NAT) activity, NAT1 and NAT2, are located on chromosome 8 at 8p21.3-23.1 and are polymorphic. Both enzymes are capable of N-acetylation, O-acetylation, and N,O-acetylation and are implicated in the activation and detoxification of known carcinogens. Single base-pair substitutions in NAT2 tend to occur in combination with other substitutions within the gene. As yet, less work has been done to characterize NAT1 allelic variants. Various methods for the detection of the reported polymorphisms exist. It is important to select a method that is appropriate to the population being studied. The functional significance of many NAT allelic variants has not been determined. Geographic and ethnic variation in the frequency of NAT2 genotypes associated with fast or intermediate acetylation has been observed. Insufficient data for NAT1 genotypes are available to reveal a clear geographic pattern. No consistent association has been found between acetylator phenotype or genotype and colorectal cancer. The lack of consistency can in part be accounted for by methodological factors, including limited statistical power. Possible interactions between the NAT genes and either environmental exposures or other polymorphic genes encoding xenobiotic metabolizing enzymes have been investigated in only a minority of these studies, and these studies have lacked statistical power to detect interactions.

Background: Low-molecular-weight heparins are attractive alternatives to unfractionated heparin (UFH) for management of unstable angina/non-Q-wave myocardial infarction (UA/NQMI)., Methods and Results: Patients (n=3910) with UA/NQMI were randomized to intravenous UFH for >/=3 days followed by subcutaneous placebo injections or uninterrupted antithrombin therapy with enoxaparin during both the acute phase (initial 30 mg intravenous bolus followed by injections of 1.0 mg/kg every 12 hours) and outpatient phase (injections every 12 hours of 40 mg for patients weighing <65 kg and 60 mg for those weighing >/=65 kg). The primary end point (death, myocardial infarction, or urgent revascularization) occurred by 8 days in 14.5% of patients in the UFH group and 12.4% of patients in the enoxaparin group (OR 0.83; 95% CI 0.69 to 1.00; P=0. 048) and by 43 days in 19.7% of the UFH group and 17.3% of the enoxaparin group (OR 0.85; 95% CI 0.72 to 1.00; P=0.048). During the first 72 hours and also throughout the entire initial hospitalization, there was no difference in the rate of major hemorrhage in the treatment groups. During the outpatient phase, major hemorrhage occurred in 1.5% of the group treated with placebo and 2.9% of the group treated with enoxaparin (P=0.021)., Conclusions: Enoxaparin is superior to UFH for reducing a composite of death and serious cardiac ischemic events during the acute management of UA/NQMI patients without causing a significant increase in the rate of major hemorrhage. No further relative decrease in events occurred with outpatient enoxaparin treatment, but there was an increase in the rate of major hemorrhage.

Context: The presence of ischemic changes on electrocardiogram (ECG) correlates with poorer outcomes in patients with acute chest pain., Objective: To determine the prognostic value of various ECG presentations of acute myocardial ischemia., Design: Retrospective analysis of the presenting ECGs of patients enrolled in Global Use of Strategies To Open Occluded Arteries in Acute Coronary Syndromes (GUSTO-IIb)., Setting: Three hundred seventy-three hospitals in 13 countries in North America, Europe, Australia, and New Zealand., Patients: A total of 12142 patients who reported symptoms of cardiac ischemia at rest within 12 hours of admission and had signs of myocardial ischemia confirmed by ECG. On presenting ECG, 22% of patients had T-wave inversion, 28% had ST-segment elevation, 35% had ST-segment depression, and 15% had a combination of ST-segment elevation and depression., Main Outcome Measure: Ability of presenting ECG to predict death or myocardial reinfarction during the first 30 days of follow-up., Results: The 30-day incidence of death or myocardial reinfarction was 5.5% in patients with T-wave inversion, 9.4% in those with ST-segment elevation, 10.5% in those with ST-segment depression, and 12.4% in those with ST-segment elevation and depression (P<.001). After adjusting for factors associated with an increased risk of 30-day death or reinfarction, compared with those who had T-wave inversion only, the odds of 30-day death or reinfarction were 1.68 (95% confidence interval [CI], 1.36-2.08) in those with ST-segment elevation, 1.62 (95% CI, 1.32-1.98) for those with ST-segment depression, and 2.27 (95% CI, 1.80-2.86) for those with combined elevation and depression. An elevated creatine kinase level at admission correlated with a higher risk of death (odds ratio [OR], 2.36; 95% CI, 1.92-2.91) and death or reinfarction (OR, 1.56; 95% CI, 1.32-1.85). The ECG category and creatine kinase level at admission remained highly predictive of death and myocardial infarction after multivariate adjustment for the significant baseline predictors of events., Conclusions: The ECG at presentation allows immediate risk stratification across the spectrum of acute coronary syndromes. An elevated creatine kinase level at admission is associated with worse outcomes.