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Sample records for alien dna introgression

  1. Mobilized retrotransposon Tos17 of rice by alien DNA introgression transposes into genes and causes structural and methylation alterations of a flanking genomic region.

    PubMed

    Han, F P; Liu, Z L; Tan, M; Hao, S; Fedak, G; Liu, B

    2004-01-01

    Tos17 is a copia-like endogenous retrotransposon of rice, which can be activated by various stresses such as tissue culture and alien DNA introgression. To confirm element mobilization by introgression and to study possible structural and epigenetic effects of Tos17 insertion on its target sequences, we isolated all flanking regions of Tos17 in an introgressed rice line (Tong35) that contains minute amount of genomic DNA from wild rice (Zizania latifolia). It was found that there has been apparent but limited mobilization of Tos17 in this introgression line, as being reflected by increased but stable copy number of the element in progeny of the line. Three of the five activated copies of the element have transposed into genes. Based on sequence analysis and Southern blot hybridization with several double-enzyme digests, no structural change in Tos17 could be inferred in the introgression line. Cytosine methylation status at all seven CCGG sites within Tos17 was also identical between the introgression line and its rice parent (Matsumae)-all sites being heavily methylated. In contrast, changes in structure and cytosine methylation patterns were detected in one of the three low-copy genomic regions that flank newly transposed Tos17, and all changes are stably inherited through selfed generations. PMID:15703040

  2. SNP Discovery for mapping alien introgressions in wheat

    PubMed Central

    2014-01-01

    Background Monitoring alien introgressions in crop plants is difficult due to the lack of genetic and molecular mapping information on the wild crop relatives. The tertiary gene pool of wheat is a very important source of genetic variability for wheat improvement against biotic and abiotic stresses. By exploring the 5Mg short arm (5MgS) of Aegilops geniculata, we can apply chromosome genomics for the discovery of SNP markers and their use for monitoring alien introgressions in wheat (Triticum aestivum L). Results The short arm of chromosome 5Mg of Ae. geniculata Roth (syn. Ae. ovata L.; 2n = 4x = 28, UgUgMgMg) was flow-sorted from a wheat line in which it is maintained as a telocentric chromosome. DNA of the sorted arm was amplified and sequenced using an Illumina Hiseq 2000 with ~45x coverage. The sequence data was used for SNP discovery against wheat homoeologous group-5 assemblies. A total of 2,178 unique, 5MgS-specific SNPs were discovered. Randomly selected samples of 59 5MgS-specific SNPs were tested (44 by KASPar assay and 15 by Sanger sequencing) and 84% were validated. Of the selected SNPs, 97% mapped to a chromosome 5Mg addition to wheat (the source of t5MgS), and 94% to 5Mg introgressed from a different accession of Ae. geniculata substituting for chromosome 5D of wheat. The validated SNPs also identified chromosome segments of 5MgS origin in a set of T5D-5Mg translocation lines; eight SNPs (25%) mapped to TA5601 [T5DL · 5DS-5MgS(0.75)] and three (8%) to TA5602 [T5DL · 5DS-5MgS (0.95)]. SNPs (gsnp_5ms83 and gsnp_5ms94), tagging chromosome T5DL · 5DS-5MgS(0.95) with the smallest introgression carrying resistance to leaf rust (Lr57) and stripe rust (Yr40), were validated in two released germplasm lines with Lr57 and Yr40 genes. Conclusion This approach should be widely applicable for the identification of species/genome-specific SNPs. The development of a large number of SNP markers will facilitate the precise introgression and

  3. Development and validation of cross-transferable and polymorphic DNA markers for detecting alien genome introgression in Oryza sativa from Oryza brachyantha.

    PubMed

    Ray, Soham; Bose, Lotan K; Ray, Joshitha; Ngangkham, Umakanta; Katara, Jawahar L; Samantaray, Sanghamitra; Behera, Lambodar; Anumalla, Mahender; Singh, Onkar N; Chen, Meingsheng; Wing, Rod A; Mohapatra, Trilochan

    2016-08-01

    African wild rice Oryza brachyantha (FF), a distant relative of cultivated rice Oryza sativa (AA), carries genes for pests and disease resistance. Molecular marker assisted alien gene introgression from this wild species to its domesticated counterpart is largely impeded due to the scarce availability of cross-transferable and polymorphic molecular markers that can clearly distinguish these two species. Availability of the whole genome sequence (WGS) of both the species provides a unique opportunity to develop markers, which are cross-transferable. We observed poor cross-transferability (~0.75 %) of O. sativa specific sequence tagged microsatellite (STMS) markers to O. brachyantha. By utilizing the genome sequence information, we developed a set of 45 low cost PCR based co-dominant polymorphic markers (STS and CAPS). These markers were found cross-transferrable (84.78 %) between the two species and could distinguish them from each other and thus allowed tracing alien genome introgression. Finally, we validated a Monosomic Alien Addition Line (MAAL) carrying chromosome 1 of O. brachyantha in O. sativa background using these markers, as a proof of concept. Hence, in this study, we have identified a set molecular marker (comprising of STMS, STS and CAPS) that are capable of detecting alien genome introgression from O. brachyantha to O. sativa. PMID:27299359

  4. Alien Introgression for FHB Resistance in Wheat - Challenges and Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over one thousand accessions of wheat relatives at different ploidy levels and wheat-alien species derivatives with varied chromosome constitutions were evaluated for Fusarium head blight (FHB) resistance. FHB resistance identified from the relatives and derivatives were introgressed into adapted br...

  5. Extensive alterations in DNA methylation and transcription in rice caused by introgression from Zizania latifolia.

    PubMed

    Liu, Zhenlan; Wang, Yongming; Shen, Ye; Guo, Wanli; Hao, Shui; Liu, Bao

    2004-03-01

    It has been demonstrated that insertion of foreign DNA into mammalian genome can profoundly alter the patterns of DNA methylation and transcription of the host genome. Introgression of alien DNA into plant genomes through sexual crossing and genetic engineering are commonly used in breeding, but it is not known if plant genomes have similar responses to alien DNA introgression as those of animals. Two stable rice lines with introgression from wild rice, Zizania latifolia, were analyzed for patterns of cytosine DNA methylation and transcription of a set of selected sequences, including cellular genes and transposable element (TE)-related DNA segments. In 21 of the 30 studied sequences, marked changes in DNA methylation and/or transcription were observed compared with those of the rice parent. In all analyzed sequences, the absence of Zizania homologues in the introgression lines was confirmed. No change in DNA methylation and expression patterns was detected in randomly selected individuals of the rice parent nor in two sibling lines without introgressed Zizania DNA. The changed methylation patterns in both introgression lines were stably maintained in all five randomly sampled individuals of a given line, as well as in selfed progenies of the lines. Changed patterns in methylation and expression were also found in an independently produced asymmetric somatic nuclear hybrid (SH6) of rice and Z. latifolia that involves a different rice genotype but also contains a small amount of Z. latifolia DNA integrated into the rice genome. Thus, we have demonstrated that alien DNA introgression into a plant genome can induce extensive alterations in DNA methylation and transcription of both cellular genes and TE-related DNA segments in a genotype-independent manner. PMID:15316290

  6. Molecular cytogenetic characterization of alien introgressions with gene Fhb3 for resistance to Fusarium head blight disease of wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) resistance was identified in the alien species Leymus racemosus, and wheat-Leymus introgression lines with FHB resistance were reported previously. Detailed molecular cytogenetic analysis of alien introgressions T01, T09, and T14 and the mapping of Fhb3, a new gene for FHB...

  7. Chromosome engineering for alien gene introgression in wheat: Progress and prospective

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chromosome engineering is a useful strategy for introgression of desirable genes from wild relatives into cultivated wheat. However, it has been a challenge to transfer a small amount of alien chromatin containing the gene of interest from one genome to another non-homologous genome through classic...

  8. Recombination is suppressed in an alien introgression in peanut harboring Rma, a dominant root-knot nematode resistance gene

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rma, a dominant root-knot nematode resistance gene introduced into tetraploid peanut (Arachis hypogaea) from a synthetic allotetraploid donor (TxAG-6), has been widely deployed in modern cultivars. The genomic location and borders of the alien chromosome segment introgressed from TxAG-6 into NemaTAM...

  9. Dynamics of mtDNA introgression during species range expansion: insights from an experimental longitudinal study.

    PubMed

    Mastrantonio, V; Porretta, D; Urbanelli, S; Crasta, G; Nascetti, G

    2016-01-01

    Introgressive hybridization represents one of the long-lasting debated genetic consequences of species range expansion. Mitochondrial DNA has been shown to heavily introgress between interbreeding animal species that meet in new sympatric areas and, often, asymmetric introgression from local to the colonizing populations has been observed. Disentangling among the evolutionary and ecological processes that might shape this pattern remains difficult, because they continuously act across time and space. In this context, long-term studies can be of paramount importance. Here, we investigated the dynamics of mitochondrial introgression between two mosquito species (Aedes mariae and Ae. zammitii ) during a colonization event that started in 1986 after a translocation experiment. By analyzing 1,659 individuals across 25 years, we showed that introgression occurred earlier and at a higher frequency in the introduced than in the local species, showing a pattern of asymmetric introgression. Throughout time, introgression increased slowly in the local species, becoming reciprocal at most sites. The rare opportunity to investigate the pattern of introgression across time during a range expansion along with the characteristics of our study-system allowed us to support a role of demographic dynamics in determining the observed introgression pattern. PMID:27460445

  10. Dynamics of mtDNA introgression during species range expansion: insights from an experimental longitudinal study

    PubMed Central

    Mastrantonio, V.; Porretta, D.; Urbanelli, S.; Crasta, G.; Nascetti, G.

    2016-01-01

    Introgressive hybridization represents one of the long-lasting debated genetic consequences of species range expansion. Mitochondrial DNA has been shown to heavily introgress between interbreeding animal species that meet in new sympatric areas and, often, asymmetric introgression from local to the colonizing populations has been observed. Disentangling among the evolutionary and ecological processes that might shape this pattern remains difficult, because they continuously act across time and space. In this context, long-term studies can be of paramount importance. Here, we investigated the dynamics of mitochondrial introgression between two mosquito species (Aedes mariae and Ae. zammitii ) during a colonization event that started in 1986 after a translocation experiment. By analyzing 1,659 individuals across 25 years, we showed that introgression occurred earlier and at a higher frequency in the introduced than in the local species, showing a pattern of asymmetric introgression. Throughout time, introgression increased slowly in the local species, becoming reciprocal at most sites. The rare opportunity to investigate the pattern of introgression across time during a range expansion along with the characteristics of our study-system allowed us to support a role of demographic dynamics in determining the observed introgression pattern. PMID:27460445

  11. Postglacial species displacement in Triturus newts deduced from asymmetrically introgressed mitochondrial DNA and ecological niche models

    PubMed Central

    2012-01-01

    Background If the geographical displacement of one species by another is accompanied by hybridization, mitochondrial DNA can introgress asymmetrically, from the outcompeted species into the invading species, over a large area. We explore this phenomenon using the two parapatric crested newt species, Triturus macedonicus and T. karelinii, distributed on the Balkan Peninsula in south-eastern Europe, as a model. Results We first delimit a ca. 54,000 km2 area in which T. macedonicus contains T. karelinii mitochondrial DNA. This introgression zone bisects the range of T. karelinii, cutting off a T. karelinii enclave. The high similarity of introgressed mitochondrial DNA haplotypes with those found in T. karelinii suggests a recent transfer across the species boundary. We then use ecological niche modeling to explore habitat suitability of the location of the present day introgression zone under current, mid-Holocene and Last Glacial Maximum conditions. This area was inhospitable during the Last Glacial Maximum for both species, but would have been habitable at the mid-Holocene. Since the mid-Holocene, habitat suitability generally increased for T. macedonicus, whereas it decreased for T. karelinii. Conclusion The presence of a T. karelinii enclave suggests that T. karelinii was the first to colonize the area where the present day introgression zone is positioned after the Last Glacial Maximum. Subsequently, we propose T. karelinii was outcompeted by T. macedonicus, which captured T. karelinii mitochondrial DNA via introgressive hybridization in the process. Ecological niche modeling suggests that this replacement was likely facilitated by a shift in climate since the mid-Holocene. We suggest that the northwestern part of the current introgression zone was probably never inhabited by T. karelinii itself, and that T. karelinii mitochondrial DNA spread there through T. macedonicus exclusively. Considering the spatial distribution of the introgressed mitochondrial DNA and

  12. Sources of stem rust resistance in wheat-alien introgression lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stem rust, caused by Puccinia graminis f. sp. tritici, is one of the most devastating diseases of wheat and the novel highly virulent race of TTKSK and its lineage are threatening wheat production worldwide. The objective of the study was to identify new sources of resistance in wheat-alien introgre...

  13. Introgression and genetic characterization of alien Fusarium head blight resistance in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alien species are an important source of genetic variability in wheat (Triticum spp.) and carry genes for resistance to numerous pathogens, including Fusarium graminearum Schwabe, the causal agent of Fusarium head blight (FHB). The goal of this project was to develop breeder-friendly, FHB-resistant ...

  14. Introgression of chromosome segments from multiple alien species in wheat breeding lines with wheat streak mosaic virus resistance.

    PubMed

    Ali, N; Heslop-Harrison, Js Pat; Ahmad, H; Graybosch, R A; Hein, G L; Schwarzacher, T

    2016-08-01

    Pyramiding of alien-derived Wheat streak mosaic virus (WSMV) resistance and resistance enhancing genes in wheat is a cost-effective and environmentally safe strategy for disease control. PCR-based markers and cytogenetic analysis with genomic in situ hybridisation were applied to identify alien chromatin in four genetically diverse populations of wheat (Triticum aestivum) lines incorporating chromosome segments from Thinopyrum intermedium and Secale cereale (rye). Out of 20 experimental lines, 10 carried Th. intermedium chromatin as T4DL*4Ai#2S translocations, while, unexpectedly, 7 lines were positive for alien chromatin (Th. intermedium or rye) on chromosome 1B. The newly described rye 1RS chromatin, transmitted from early in the pedigree, was associated with enhanced WSMV resistance. Under field conditions, the 1RS chromatin alone showed some resistance, while together with the Th. intermedium 4Ai#2S offered superior resistance to that demonstrated by the known resistant cultivar Mace. Most alien wheat lines carry whole chromosome arms, and it is notable that these lines showed intra-arm recombination within the 1BS arm. The translocation breakpoints between 1BS and alien chromatin fell in three categories: (i) at or near to the centromere, (ii) intercalary between markers UL-Thin5 and Xgwm1130 and (iii) towards the telomere between Xgwm0911 and Xbarc194. Labelled genomic Th. intermedium DNA hybridised to the rye 1RS chromatin under high stringency conditions, indicating the presence of shared tandem repeats among the cereals. The novel small alien fragments may explain the difficulty in developing well-adapted lines carrying Wsm1 despite improved tolerance to the virus. The results will facilitate directed chromosome engineering producing agronomically desirable WSMV-resistant germplasm. PMID:27245423

  15. Exploring the Effect of Asymmetric Mitochondrial DNA Introgression on Estimating Niche Divergence in Morphologically Cryptic Species

    PubMed Central

    Wielstra, Ben; Arntzen, Jan W.

    2014-01-01

    If potential morphologically cryptic species, identified based on differentiated mitochondrial DNA, express ecological divergence, this increases support for their treatment as distinct species. However, mitochondrial DNA introgression hampers the correct estimation of ecological divergence. We test the hypothesis that estimated niche divergence differs when considering nuclear DNA composition or mitochondrial DNA type as representing the true species range. We use empirical data of two crested newt species (Amphibia: Triturus) which possess introgressed mitochondrial DNA from a third species in part of their ranges. We analyze the data in environmental space by determining Fisher distances in a principal component analysis and in geographical space by determining geographical overlap of species distribution models. We find that under mtDNA guidance in one of the two study cases niche divergence is overestimated, whereas in the other it is underestimated. In the light of our results we discuss the role of estimated niche divergence in species delineation. PMID:24743746

  16. The Elusive Nature of Adaptive Mitochondrial DNA Evolution of an Arctic Lineage Prone to Frequent Introgression

    PubMed Central

    Melo-Ferreira, José; Vilela, Joana; Fonseca, Miguel M.; da Fonseca, Rute R.; Boursot, Pierre; Alves, Paulo C.

    2014-01-01

    Mitochondria play a fundamental role in cellular metabolism, being responsible for most of the energy production of the cell in the oxidative phosphorylation (OXPHOS) pathway. Mitochondrial DNA (mtDNA) encodes for key components of this process, but its direct role in adaptation remains far from understood. Hares (Lepus spp.) are privileged models to study the impact of natural selection on mitogenomic evolution because 1) species are adapted to contrasting environments, including arctic, with different metabolic pressures, and 2) mtDNA introgression from arctic into temperate species is widespread. Here, we analyzed the sequences of 11 complete mitogenomes (ten newly obtained) of hares of temperate and arctic origins (including two of arctic origin introgressed into temperate species). The analysis of patterns of codon substitutions along the reconstructed phylogeny showed evidence for positive selection in several codons in genes of the OXPHOS complexes, most notably affecting the arctic lineage. However, using theoretical models, no predictable effect of these differences was found on the structure and physicochemical properties of the encoded proteins, suggesting that the focus of selection may lie on complex interactions with nuclear encoded peptides. Also, a cloverleaf structure was detected in the control region only from the arctic mtDNA lineage, which may influence mtDNA replication and transcription. These results suggest that adaptation impacted the evolution of hare mtDNA and may have influenced the occurrence and consequences of the many reported cases of massive mtDNA introgression. However, the origin of adaptation remains elusive. PMID:24696399

  17. Introgression of chromosome segments from multiple alien species in wheat breeding lines with wheat streak mosaic virus resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pyramiding of alien-derived Wheat streak mosaic virus (WSMV) resistance and resistance enhancing genes in wheat is a costeffective and environmentally safe strategy for disease control. PCR-based markers and cytogenetic analysis with genomic in situ hybridisation were applied to identify alien chrom...

  18. Male-killing Wolbachia and mitochondrial DNA: selective sweeps, hybrid introgression and parasite population dynamics.

    PubMed Central

    Jiggins, Francis M

    2003-01-01

    Mitochondrial DNA (mtDNA) sequences are widely used as neutral genetic markers in insects. However, patterns of mtDNA variability are confounded by the spread of maternally transmitted parasites, which are genetically linked to the mitochondria. We have investigated these effects in the butterflies Acraea encedon (which is host to two strains of male-killing Wolbachia bacteria) and A. encedana (which is host to one strain). Within a population, the mitochondria are in linkage disequilibrium with the different male-killers. Furthermore, there has been a recent selective sweep of the mtDNA, which has led to the loss of mitochondrial variation within populations and erased any geographical structure. We also found that one of the male-killers, together with the associated mtDNA, has introgressed from A. encedana into A. encedon within the last 16,000 years. Interestingly, because butterflies are female heterogametic, this will presumably have also led to the introgression of genes on the W sex chromosome. Finally, in A. encedon the mitochondria in uninfected females are unaltered by the spread of the male-killer and have diverse, geographically structured mtDNA. This means we can reject the hypothesis that the male-killer is at a stable equilibrium maintained by imperfect transmission of the bacterium. Instead, some other form of balancing selection may be maintaining uninfected females in the population and preventing the species from going extinct due to a shortage of males. PMID:12750316

  19. Hybridization and Introgression among Species of Sunfish (Lepomis): Analysis by Mitochondrial DNA and Allozyme Markers

    PubMed Central

    Avise, John C.; Saunders, Nancy C.

    1984-01-01

    We explore the potential of mitochondrial DNA (mtDNA) analysis, alone and in conjunction with allozymes, to study low-frequency hybridization and introgression phenomena in natural populations. MtDNAs from small samples of nine species of sunfish (Lepomis, Centrarchidae) were purified and digested with each of 13 informative restriction enzymes. Digestion profiles for all species were highly distinct: estimates of overall fragment homology between pairs of species ranged from 0–36%. Allozymes encoded by nine nuclear genes also showed large frequency differences among species and together with mtDNA provided many genetic markers for hybrid identification. A genetic analysis of 277 sunfish from two locations in north Georgia revealed the following: (1) a low frequency of interspecific hybrids, all of which appeared to be F1's; (2) the involvement of five sympatric Lepomis species in the production of these hybrids; (3) no evidence for introgression between species in our study locales (although for rare hybridization, most later-generation backcrosses would not be reliably distinguished from parentals); (4) a tendency for hybridizations to take place preferentially between parental species differing greatly in abundance; (5) a tendency for the rare species in a hybrid cross to provide the female parent. Our data suggest that absence of conspecific pairing partners and mating stimuli for females of rarer species may be important factors in increasing the likelihood of interspecific hybridization. The maternal inheritance of mtDNA offers at least two novel advantages for hybridization analysis: (1) an opportunity to determine direction in hybrid crosses; and (2) due to the linkage among mtDNA markers, an increased potential to distinguish effects of introgression from symplesiomorphy or character convergence. PMID:6090268

  20. Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA.

    PubMed

    Huerta-Sánchez, Emilia; Jin, Xin; Asan; Bianba, Zhuoma; Peter, Benjamin M; Vinckenbosch, Nicolas; Liang, Yu; Yi, Xin; He, Mingze; Somel, Mehmet; Ni, Peixiang; Wang, Bo; Ou, Xiaohua; Huasang; Luosang, Jiangbai; Cuo, Zha Xi Ping; Li, Kui; Gao, Guoyi; Yin, Ye; Wang, Wei; Zhang, Xiuqing; Xu, Xun; Yang, Huanming; Li, Yingrui; Wang, Jian; Wang, Jun; Nielsen, Rasmus

    2014-08-14

    As modern humans migrated out of Africa, they encountered many new environmental conditions, including greater temperature extremes, different pathogens and higher altitudes. These diverse environments are likely to have acted as agents of natural selection and to have led to local adaptations. One of the most celebrated examples in humans is the adaptation of Tibetans to the hypoxic environment of the high-altitude Tibetan plateau. A hypoxia pathway gene, EPAS1, was previously identified as having the most extreme signature of positive selection in Tibetans, and was shown to be associated with differences in haemoglobin concentration at high altitude. Re-sequencing the region around EPAS1 in 40 Tibetan and 40 Han individuals, we find that this gene has a highly unusual haplotype structure that can only be convincingly explained by introgression of DNA from Denisovan or Denisovan-related individuals into humans. Scanning a larger set of worldwide populations, we find that the selected haplotype is only found in Denisovans and in Tibetans, and at very low frequency among Han Chinese. Furthermore, the length of the haplotype, and the fact that it is not found in any other populations, makes it unlikely that the haplotype sharing between Tibetans and Denisovans was caused by incomplete ancestral lineage sorting rather than introgression. Our findings illustrate that admixture with other hominin species has provided genetic variation that helped humans to adapt to new environments. PMID:25043035

  1. Large-scale asymmetric introgression of cytoplasmic DNA reveals Holocene range displacement in a North American boreal pine complex.

    PubMed

    Godbout, Julie; Yeh, Francis C; Bousquet, Jean

    2012-08-01

    Jack pine (Pinus banksiana) and lodgepole pine (Pinus contorta var. latifolia) are two North American boreal hard pines that hybridize in their zone of contact in western Canada. The main objective of this study was to characterize their patterns of introgression resulting from past and recent gene flow, using cytoplasmic markers having maternal or paternal inheritance. Mitochondrial DNA (mtDNA) and chloroplast DNA (cpDNA) diversity was assessed in allopatric populations of each species and in stands from the current zone of contact containing morphological hybrids. Cluster analyses were used to identify genetic discontinuities among groups of populations. A canonical analysis was also conducted to detect putative associations among cytoplasmic DNA variation, tree morphology, and site ecological features. MtDNA introgression was extensive and asymmetric: it was detected in P. banksiana populations from the hybrid zone and from allopatric areas, but not in P. contorta populations. Very weak cpDNA introgression was observed, and only in P. banksiana populations. The mtDNA introgression pattern indicated that central Canada was first colonized by migrants from a P. contorta glacial population located west of the Rocky Mountains, before being replaced by P. banksiana migrating westward during the Holocene. In contrast, extensive pollen gene flow would have erased the cpDNA traces of this ancient presence of P. contorta. Additional evidence for this process was provided by the results of canonical analysis, which indicated that the current cpDNA background of trees reflected recent pollen gene flow from the surrounding dominant species rather than historical events that took place during the postglacial colonization. PMID:22957188

  2. Extent and pattern of DNA methylation alteration in rice lines derived from introgressive hybridization of rice and Zizania latifolia Griseb.

    PubMed

    Dong, Z Y; Wang, Y M; Zhang, Z J; Shen, Y; Lin, X Y; Ou, X F; Han, F P; Liu, B

    2006-07-01

    We have reported previously that introgression by Zizania latifolia resulted in extensive DNA methylation changes in the recipient rice genome, as detected by a set of pre-selected DNA segments. In this study, using the methylation-sensitive amplified polymorphism (MSAP) method, we globally assessed the extent and pattern of cytosine methylation alterations in three typical introgression lines relative to their rice parent at approximately 2,700 unbiased genomic loci each representing a recognition site cleaved by one or both of the isoschizomers, HpaII/MspI. Based on differential digestion by the isoschizomers, it is estimated that 15.9% of CCGG sites are either fully methylated at the internal Cs and/or hemi-methylated at the external Cs in the rice parental cultivar Matsumae. In comparison, a statistically significant increase in the overall level of both methylation types was detected in all three studied introgression lines (19.2, 18.6, 19.6%, respectively). Based on comparisons of MSAP profiles between the isoschizomers within the rice parent and between parent and the introgression lines, four major groups of MSAP banding patterns are recognized, which can be further divided into various subgroups as a result of inheritance of, or variation in, parental methylation patterns. The altered methylation patterns include hyper- and hypomethylation changes, as well as inter-conversion of hemi- to full-methylation, or vice versa, at the relevant CCGG site(s). Most alterations revealed by MSAP in low-copy loci can be validated by DNA gel blot analysis. The changed methylation patterns are uniform among randomly selected individuals for a given introgression line within or among selfed generations. Sequencing on 31 isolated fragments that showed different changing patterns in the introgression line(s) allowed their mapping onto variable regions on one or more of the 12 rice chromosomes. These segments include protein-coding genes, transposon/retrotransposons and

  3. Interspecific Introgression in Cetaceans: DNA Markers Reveal Post-F1 Status of a Pilot Whale

    PubMed Central

    Miralles, Laura; Lens, Santiago; Rodríguez-Folgar, Antonio; Carrillo, Manuel; Martín, Vidal; Mikkelsen, Bjarni; Garcia-Vazquez, Eva

    2013-01-01

    Visual species identification of cetacean strandings is difficult, especially when dead specimens are degraded and/or species are morphologically similar. The two recognised pilot whale species (Globicephala melas and Globicephala macrorhynchus) are sympatric in the North Atlantic Ocean. These species are very similar in external appearance and their morphometric characteristics partially overlap; thus visual identification is not always reliable. Genetic species identification ensures correct identification of specimens. Here we have employed one mitochondrial (D-Loop region) and eight nuclear loci (microsatellites) as genetic markers to identify six stranded pilot whales found in Galicia (Northwest Spain), one of them of ambiguous phenotype. DNA analyses yielded positive amplification of all loci and enabled species identification. Nuclear microsatellite DNA genotypes revealed mixed ancestry for one individual, identified as a post-F1 interspecific hybrid employing two different Bayesian methods. From the mitochondrial sequence the maternal species was Globicephala melas. This is the first hybrid documented between Globicephala melas and G. macrorhynchus, and the first post-F1 hybrid genetically identified between cetaceans, revealing interspecific genetic introgression in marine mammals. We propose to add nuclear loci to genetic databases for cetacean species identification in order to detect hybrid individuals. PMID:23990883

  4. Assessment of cattle genetic introgression into domestic yak populations using mitochondrial and microsatellite DNA markers

    PubMed Central

    Qi, X B; Jianlin, H; Wang, G; Rege, J E O; Hanotte, O

    2010-01-01

    Hybridization between yak Poephagus grunniens and taurine Bos taurus or indicine B. indicus cattle has been widely practiced throughout the yak geographical range, and gene flow is expected to have occurred between these species. To assess the impact of cattle admixture on domestic yak, we examined 1076 domestic yak from 29 populations collected in China, Bhutan, Nepal, India, Pakistan, Kyrgyzstan, Mongolia and Russia using mitochondrial DNA and 17 autosomal microsatellite loci. A cattle diagnostic marker-based analysis reveals cattle-specific mtDNA and/or autosomal microsatellite allele introgression in 127 yak individuals from 22 populations. The mean level of cattle admixture across the populations, calculated using allelic information at 17 autosomal microsatellite loci, remains relatively low (mYcattle = 2.66 ± 0.53% and Qcattle = 0.69 ± 2.58%), although it varies a lot across populations as well as among individuals within population. Although the level of cattle admixture shows a clear geographical structure, with higher levels of admixture in the Qinghai-Tibetan Plateau and Mongolian and Russian regions, and lower levels in the Himalayan and Pamir Plateau region, our results indicate that the level of cattle admixture is not significantly correlated with the altitude across geographical regions as well as within geographical region. Although yak-cattle hybridization is primarily driven to produce F1 hybrids, our results show that the subsequent gene flow between yak and cattle took place and has affected contemporary genetic make-up of domestic yak. To protect yak genetic integrity, hybridization between yak and cattle should be tightly controlled. PMID:19917041

  5. Introgression of wheat DNA markers from A, B and D genomes in early generation progeny of Aegilops cylindrica Host x Triticum aestivum L. hybrids.

    PubMed

    Schoenenberger, N; Felber, F; Savova-Bianchi, D; Guadagnuolo, R

    2005-11-01

    Introgression from allohexaploid wheat (Triticum aestivum L., AABBDD) to allotetraploid jointed goatgrass (Aegilops cylindrica Host, CCDD) can take place in areas where the two species grow in sympatry and hybridize. Wheat and Ae. cylindrica share the D genome, issued from the common diploid ancestor Aegilops tauschii Coss. It has been proposed that the A and B genome of bread wheat are secure places to insert transgenes to avoid their introgression into Ae. cylindrica because during meiosis in pentaploid hybrids, A and B genome chromosomes form univalents and tend to be eliminated whereas recombination takes place only in D genome chromosomes. Wheat random amplified polymorphic DNA (RAPD) fragments, detected in intergeneric hybrids and introgressed to the first backcross generation with Ae. cylindrica as the recurrent parent and having a euploid Ae. cylindrica chromosome number or one supernumerary chromosome, were assigned to wheat chromosomes using Chinese Spring nulli-tetrasomic wheat lines. Introgressed fragments were not limited to the D genome of wheat, but specific fragments of A and B genomes were also present in the BC1. Their presence indicates that DNA from any of the wheat genomes can introgress into Ae. cylindrica. Successfully located RAPD fragments were then converted into highly specific and easy-to-use sequence characterised amplified regions (SCARs) through sequencing and primer design. Subsequently these markers were used to characterise introgression of wheat DNA into a BC1S1 family. Implications for risk assessment of genetically modified wheat are discussed. PMID:16133306

  6. Registration of a hard red winter wheat genetic stock homozygous for ph1b for facilitating alien introgression for crop improvement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild relatives of bread wheat, Triticum aestivum L. are an important source for disease and pest resistance that can be exploited in wheat improvement. However, in wheat/alien species hybrids the pairing homoeologous gene, Ph1, suppresses the pairing and recombination of wheat and alien chromosomes,...

  7. Characterization and mapping of cryptic alien introgression from Aegilops geniculata with new leaf rust and stripe rust resistance genes Lr57 and Yr40 in wheat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf rust and stripe rust are important foliar diseases of wheat worldwide. Leaf rust and stripe rust resistant introgression lines were developed by induced homoeologous chromosome pairing between wheat chromosome 5D and 5Mg of Aegilops geniculata (UgMg). Characterization of rust resistant BC2F5 a...

  8. The hidden history of the snowshoe hare, Lepus americanus: extensive mitochondrial DNA introgression inferred from multilocus genetic variation.

    PubMed

    Melo-Ferreira, José; Seixas, Fernando A; Cheng, Ellen; Mills, L Scott; Alves, Paulo C

    2014-09-01

    Hybridization drives the evolutionary trajectory of many species or local populations, and assessing the geographic extent and genetic impact of interspecific gene flow may provide invaluable clues to understand population divergence or the adaptive relevance of admixture. In North America, hares (Lepus spp.) are key species for ecosystem dynamics and their evolutionary history may have been affected by hybridization. Here we reconstructed the speciation history of the three most widespread hares in North America - the snowshoe hare (Lepus americanus), the white-tailed jackrabbit (L. townsendii) and the black-tailed jackrabbit (L. californicus) - by analysing sequence variation at eight nuclear markers and one mitochondrial DNA (mtDNA) locus (6240 bp; 94 specimens). A multilocus-multispecies coalescent-based phylogeny suggests that L. americanus diverged ~2.7 Ma and that L. californicus and L. townsendii split more recently (~1.2 Ma). Within L. americanus, a deep history of cryptic divergence (~2.0 Ma) was inferred, which coincides with major speciation events in other North American species. While the isolation-with-migration model suggested that nuclear gene flow was generally rare or absent among species or major genetic groups, coalescent simulations of mtDNA divergence revealed historical mtDNA introgression from L. californicus into the Pacific Northwest populations of L. americanus. This finding marks a history of past reticulation between these species, which may have affected other parts of the genome and influence the adaptive potential of hares during climate change. PMID:25113393

  9. Hybridization and massive mtDNA unidirectional introgression between the closely related Neotropical toads Rhinella marina and R. schneideri inferred from mtDNA and nuclear markers

    PubMed Central

    2011-01-01

    Background The classical perspective that interspecific hybridization in animals is rare has been changing due to a growing list of empirical examples showing the occurrence of gene flow between closely related species. Using sequence data from cyt b mitochondrial gene and three intron nuclear genes (RPL9, c-myc, and RPL3) we investigated patterns of nucleotide polymorphism and divergence between two closely related toad species R. marina and R. schneideri. By comparing levels of differentiation at nuclear and mtDNA levels we were able to describe patterns of introgression and infer the history of hybridization between these species. Results All nuclear loci are essentially concordant in revealing two well differentiated groups of haplotypes, corresponding to the morphologically-defined species R. marina and R. schneideri. Mitochondrial DNA analysis also revealed two well-differentiated groups of haplotypes but, in stark contrast with the nuclear genealogies, all R. schneideri sequences are clustered with sequences of R. marina from the right Amazon bank (RAB), while R. marina sequences from the left Amazon bank (LAB) are monophyletic. An Isolation-with-Migration (IM) analysis using nuclear data showed that R. marina and R. schneideri diverged at ≈ 1.69 Myr (early Pleistocene), while R. marina populations from LAB and RAB diverged at ≈ 0.33 Myr (middle Pleistocene). This time of divergence is not consistent with the split between LAB and RAB populations obtained with mtDNA data (≈ 1.59 Myr), which is notably similar to the estimate obtained with nuclear genes between R. marina and R. schneideri. Coalescent simulations of mtDNA phylogeny under the speciation history inferred from nuclear genes rejected the hypothesis of incomplete lineage sorting to explain the conflicting signal between mtDNA and nuclear-based phylogenies. Conclusions The cytonuclear discordance seems to reflect the occurrence of interspecific hybridization between these two closely related

  10. Mitochondrial and nuclear DNA analysis revealed a cryptic species and genetic introgression in Littorina sitkana (Mollusca, Gastropoda).

    PubMed

    Azuma, Noriko; Yamazaki, Tomoyasu; Chiba, Susumu

    2011-12-01

    We investigated mitochondrial and nuclear DNA genotypes in nominal Littorina sitkana samples from 2 localities in Eastern Hokkaido, northern Japan. Our results indicated the existence of cryptic species. In the analysis of partial mitochondrial Cytchrome b gene sequences, haplotypes of L. sitkana samples were monophyletic in a phylogenetic tree with orthologous sequences from other Littorina species, but were apparently separated in 2 clades. One included typical L. sitkana (CBa clade) samples, which formed a clade with an allopatric species, L. horikawai. The other, CBb, was independent from CBa and L. horikawai. Haplotypes of the mitochondrial 16S rRNA gene also separated into 2 clades. We additionally examined intron sequence of the heat shock cognate 70 (HSC70) nuclear gene and identified 17 haplotypes. These were also separated into 2 clades, HSCa and HSCb. Among the examined Hokkaido samples, 60% of individuals were heterozygotes. However, each heterozygote consisted of haplotypes from the same clade, HSCa or HSCb, and no admixture of HSCa and HSCb haplotypes was observed. These results indicate reproductive isolation between the 2 clades. Among the genotyped Hokkaido samples, 93% of individuals had CBa + HSCa or CBb + HSCb genotypes, and 7% had CBb + HSCa genotypes. The discrepancy between the mtDNA and nuclear DNA haplotypes in a few individuals may have been caused by genetic introgression due to past hybridization. PMID:22374127

  11. Introgression browser: high-throughput whole-genome SNP visualization.

    PubMed

    Aflitos, Saulo Alves; Sanchez-Perez, Gabino; de Ridder, Dick; Fransz, Paul; Schranz, Michael E; de Jong, Hans; Peters, Sander A

    2015-04-01

    Breeding by introgressive hybridization is a pivotal strategy to broaden the genetic basis of crops. Usually, the desired traits are monitored in consecutive crossing generations by marker-assisted selection, but their analyses fail in chromosome regions where crossover recombinants are rare or not viable. Here, we present the Introgression Browser (iBrowser), a bioinformatics tool aimed at visualizing introgressions at nucleotide or SNP (Single Nucleotide Polymorphisms) accuracy. The software selects homozygous SNPs from Variant Call Format (VCF) information and filters out heterozygous SNPs, multi-nucleotide polymorphisms (MNPs) and insertion-deletions (InDels). For data analysis iBrowser makes use of sliding windows, but if needed it can generate any desired fragmentation pattern through General Feature Format (GFF) information. In an example of tomato (Solanum lycopersicum) accessions we visualize SNP patterns and elucidate both position and boundaries of the introgressions. We also show that our tool is capable of identifying alien DNA in a panel of the closely related S. pimpinellifolium by examining phylogenetic relationships of the introgressed segments in tomato. In a third example, we demonstrate the power of the iBrowser in a panel of 597 Arabidopsis accessions, detecting the boundaries of a SNP-free region around a polymorphic 1.17 Mbp inverted segment on the short arm of chromosome 4. The architecture and functionality of iBrowser makes the software appropriate for a broad set of analyses including SNP mining, genome structure analysis, and pedigree analysis. Its functionality, together with the capability to process large data sets and efficient visualization of sequence variation, makes iBrowser a valuable breeding tool. PMID:25704554

  12. Isolation and characterization of a set of disease resistance-gene analogs (RGAs) from wild rice, Zizania latifolia Griseb. I. Introgression, copy number lability, sequence change, and DNA methylation alteration in several rice-Zizania introgression lines.

    PubMed

    Chen, Yu; Long, Likun; Lin, Xiuyun; Guo, Wanli; Liu, Bao

    2006-02-01

    Eight resistance-gene analogs (RGAs) were isolated from wild rice, Zizania latifolia Griseb., by degenerate primers designed according to conserved motifs at or around the nucleotide-binding site (NBS) of known NBS-containing plant resistance genes. The 8 RGAs were classified into 6 distinct groups based on their deduced amino acid sequence similarity of 60% or greater. Gel-blot hybridization of each of the RGAs to 4 rice - Z. latifolia intro gression lines indicated an array of changes at either introgressed Zizania RGAs or, more likely, their rice homologs. The changes included dramatic increase in copy number, modification at the primary DNA sequence, and alteration in DNA methylation patterns. PMID:16498465

  13. Extensive de Novo genomic variation in rice induced by introgression from wild rice (Zizania latifolia Griseb.).

    PubMed

    Wang, Yong-Ming; Dong, Zhen-Ying; Zhang, Zhong-Juan; Lin, Xiu-Yun; Shen, Ye; Zhou, Daowei; Liu, Bao

    2005-08-01

    To study the possible impact of alien introgression on a recipient plant genome, we examined >6000 unbiased genomic loci of three stable rice recombinant inbred lines (RILs) derived from intergeneric hybridization between rice (cv. Matsumae) and a wild relative (Zizania latifolia Griseb.) followed by successive selfing. Results from amplified fragment length polymorphism (AFLP) analysis showed that, whereas the introgressed Zizania DNA comprised <0.1% of the genome content in the RILs, extensive and genome-wide de novo variations occurred in up to 30% of the analyzed loci for all three lines studied. The AFLP-detected changes were validated by DNA gel-blot hybridization and/or sequence analysis of genomic loci corresponding to a subset of the differentiating AFLP fragments. A BLAST analysis revealed that the genomic variations occurred in diverse sequences, including protein-coding genes, transposable elements, and sequences of unknown functions. Pairwise sequence comparison of selected loci between a RIL and its rice parent showed that the variations represented either base substitutions or small insertion/deletions. Genome variations were detected in all 12 rice chromosomes, although their distribution was uneven both among and within chromosomes. Taken together, our results imply that even cryptic alien introgression can be highly mutagenic to a recipient plant genome. PMID:15937131

  14. Introgression of coyote mitochondrial DNA into sympatric North American gray wolf populations

    USGS Publications Warehouse

    Lehman, N.; Eisenhawer, A.; Hansen, K.; Mech, L.D.; Peterson, R.O.; Gogan, P.J.P.; Wayne, R.K.

    1991-01-01

    Mitochondrial DNA (mtDNA) genotypes of gray wolves and coyotes from localities throughout North America were determined using restriction fragment length polymorphisms. Of the 13 genotypes found among the wolves, 7 are clearly of coyote origin, indicating that genetic transfer of coyote mtDNA into wolf populations has occurred through hybridization. The transfer of mtDNA appears unidirectional from coyotes into wolves because no coyotes sampled have a wolf-derived mtDNA genotype. Wolves possessing coyote-derived genotypes are confined to a contiguous geographic region in Minnesota, Ontario, and Quebec, and the frequency of coyote-type mtDNA in these wolf populations is high (>50%). The ecological history of the hybrid zone suggests that hybridization is taking place in regions where coyotes have only recently become abundant following conversion of forests to farmlands. Dispersing male wolves unable to find conspecific mates may be pairing with female coyotes in deforested areas bordering wolf territories. Our results demonstrate that closely related species of mobile terrestrial vertebrates have the potential for extensive genetic exchange when ecological conditions change suddenly.

  15. Induced and constitutive DNA methylation in a salinity-tolerant wheat introgression line.

    PubMed

    Wang, Meng; Qin, Lumin; Xie, Chao; Li, Wei; Yuan, Jiarui; Kong, Lina; Yu, Wenlong; Xia, Guangmin; Liu, Shuwei

    2014-07-01

    Cytosine methylation is a well recognized epigenetic mark. Here, the methylation status of a salinity-tolerant wheat cultivar (cv. SR3, derived from a somatic hybridization event) and its progenitor parent (cv. JN177) was explored both globally and within a set of 24 genes responsive to salinity stress. A further comparison was made between DNA extracted from plants grown under control conditions and when challenged by salinity stress. The SR3 and JN177 genomes differed with respect to their global methylation level, and methylation levels were reduced by exposure to salinity stress. We found the genetic stress- (triggered by a combination of different genomes in somatic hybridization) induced methylation pattern of 13 loci in non-stressed SR3; the same 13 loci were found to undergo methylation in salinity-stressed JN177. For the salinity-responsive genes, SR3 and JN177 also showed different methylation modifications. C methylation polymorphisms induced by salinity stress were present in both the promoter and coding regions of some of the 24 selected genes, but only the former were associated with changes in transcript abundance. The expression of both TaFLS1 (encoding a flavonol synthase) and TaWRSI5 (encoding a Bowman-Birk-type protease inhibitor), which showed both a different expression and a different DNA methylation level between SR3 and JN177, enhanced the salinity tolerance of Arabidopsis thaliana. C methylation changes appear to be a common component of the plant response to stress, and methylation changes triggered by somatic hybridization may contribute to the superior salinity tolerance of SR3. PMID:24793752

  16. Effects of asymmetric nuclear introgression, introgressive mitochondrial sweep, and purifying selection on phylogenetic reconstruction and divergence estimates in the Pacific clade of Locustella warblers.

    PubMed

    Drovetski, Sergei V; Semenov, Georgy; Red'kin, Yaroslav A; Sotnikov, Vladimir N; Fadeev, Igor V; Koblik, Evgeniy A

    2015-01-01

    When isolated but reproductively compatible populations expand geographically and meet, simulations predict asymmetric introgression of neutral loci from a local to invading taxon. Genetic introgression may affect phylogenetic reconstruction by obscuring topology and divergence estimates. We combined phylogenetic analysis of sequences from one mtDNA and 12 nuDNA loci with analysis of gene flow among 5 species of Pacific Locustella warblers to test for presence of genetic introgression and its effects on tree topology and divergence estimates. Our data showed that nuDNA introgression was substantial and asymmetrical among all members of superspecies groups whereas mtDNA showed no introgression except a single species pair where the invader's mtDNA was swept by mtDNA of the local species. This introgressive sweep of mtDNA had the opposite direction of the nuDNA introgression and resulted in the paraphyly of the local species' mtDNA haplotypes with respect to those of the invader. Тhe multilocus nuDNA species tree resolved all inter- and intraspecific relationships despite substantial introgression. However, the node ages on the species tree may be underestimated as suggested by the differences in node age estimates based on non-introgressing mtDNA and introgressing nuDNA. In turn, the introgressive sweep and strong purifying selection appear to elongate internal branches in the mtDNA gene tree. PMID:25849039

  17. Evidence for archaic adaptive introgression in humans

    PubMed Central

    Racimo, Fernando; Sankararaman, Sriram; Nielsen, Rasmus; Huerta-Sánchez, Emilia

    2015-01-01

    As modern and ancient DNA sequence data from diverse human populations accumulate1–4, evidence is increasing in support of the existence of beneficial variants acquired from archaic humans that may have accelerated adaptation and improved survival in new environments — a process, known as adaptive introgression (AI). Within the past couple of years, a series of studies5–8 have identified genomic regions showing strong evidence for archaic adaptive introgression. In this Review, we provide an overview of the statistical methods developed to identify archaic introgressed fragments in the genome sequences of modern humans, and to determine whether positive selection has acted on these fragments. We discuss recently reported examples of adaptive introgression and consider the level of supporting evidence for each, grouped by selection pressure. We discuss challenges and recommendations for inferring selection on introgressed regions. PMID:25963373

  18. The coregulator Alien

    PubMed Central

    Papaioannou, Maria; Melle, Christian; Baniahmad, Aria

    2007-01-01

    Alien has characteristics of a corepressor for selected members of the nuclear hormone receptor (NHR) superfamily and also for transcription factors involved in cell cycle regulation and DNA repair. Alien mediates gene silencing and represses the transactivation of specific NHRs and other transcription factors to modulate hormone response and cell proliferation. Alien is a highly conserved protein and is expressed in a wide variety of tissues. Knockout of the gene encoding Alien in mice is embryonic lethal at a very early stage, indicating an important evolutionary role in multicellular organisms. From a mechanistic perspective, the corepressor function of Alien is in part mediated by histone deacetylase (HDAC) activity. In addition, Alien seems to modulate nucleosome assembly activity. This suggests that Alien is acting on chromatin not only through recruitment of histone-modifying activities, but also through enhancing nucleosome assembly. PMID:18174916

  19. Lack of Genotype and Phenotype Correlation in a Rice T-DNA Tagged Line Is Likely Caused by Introgression in the Seed Source.

    PubMed

    Wei, Fu-Jin; Tsai, Yuan-Ching; Hsu, Yu-Ming; Chen, Yu-An; Huang, Ching-Ting; Wu, Hshin-Ping; Huang, Lin-Tzu; Lai, Ming-Hsin; Kuang, Lin-Yun; Lo, Shuen-Fang; Yu, Su-May; Lin, Yann-Rong; Hsing, Yue-Ie Caroline

    2016-01-01

    Rice (Oryza sativa) is one of the most important crops in the world. Several rice insertional mutant libraries are publicly available for systematic analysis of gene functions. However, the tagging efficiency of these mutant resources-the relationship between genotype and phenotype-is very low. We used whole-genome sequencing to analyze a T-DNA-tagged transformant from the Taiwan Rice Insertional Mutants (TRIM) resource. The phenomics records for M0028590, one of the TRIM lines, revealed three phenotypes-wild type, large grains, and tillering dwarf-in the 12 T1 plants. Using the sequencing data for 7 plants from three generations of this specific line, we demonstrate that introgression from an indica rice variety might occur in one generation before the seed was used for callus generation and transformation of this line. In addition, the large-grain trait came from the GS3 gene of the introgressed region and the tillering dwarf phenotype came from a single nucleotide change in the D17 gene that occurred during the callus induction to regeneration of the transformant. As well, another regenerant showed completely heterozygous single-nucleotide polymorphisms across the whole genome. In addition to the known sequence changes such as T-DNA integration, single nucleotide polymorphism, insertion, deletion, chromosome rearrangement and doubling, spontaneous outcrossing occurred in the rice field may also explain some mutated traits in a tagged mutant population. Thus, the co-segregation of an integration event and the phenotype should be checked when using these mutant populations. PMID:27186981

  20. Genomic Change, Retrotransposon Mobilization and Extensive Cytosine Methylation Alteration in Brassica napus Introgressions from Two Intertribal Hybridizations

    PubMed Central

    Zhang, Xueli; Ge, Xianhong; Shao, Yujiao; Sun, Genlou; Li, Zaiyun

    2013-01-01

    Hybridization and introgression represent important means for the transfer and/or de novo origination of traits and play an important role in facilitating speciation and plant breeding. Two sets of introgression lines in Brassica napus L. were previously established by its intertribal hybridizations with two wild species and long-term selection. In this study, the methods of amplified fragment length polymorphisms (AFLP), sequence-specific amplification polymorphism (SSAP) and methylation-sensitive amplified polymorphism (MSAP) were used to determine their genomic change, retrotransposon mobilization and cytosine methylation alteration in these lines. The genomic change revealed by the loss or gain of AFLP bands occurred for ∼10% of the total bands amplified in the two sets of introgressions, while no bands specific for wild species were detected. The new and absent SSAP bands appeared for 9 out of 11 retrotransposons analyzed, with low frequency of new bands and their total percentage of about 5% in both sets. MSAP analysis indicated that methylation changes were common in these lines (33.4–39.8%) and the hypermethylation was more frequent than hypomethylation. Our results suggested that certain extents of genetic and epigenetic alterations were induced by hybridization and alien DNA introgression. The cryptic mechanism of these changes and potential application of these lines in breeding were also discussed. PMID:23468861

  1. Lack of Genotype and Phenotype Correlation in a Rice T-DNA Tagged Line Is Likely Caused by Introgression in the Seed Source

    PubMed Central

    Wei, Fu-Jin; Tsai, Yuan-Ching; Hsu, Yu-Ming; Chen, Yu-An; Huang, Ching-Ting; Wu, Hshin-Ping; Huang, Lin-Tzu; Lai, Ming-Hsin; Kuang, Lin-Yun; Lo, Shuen-Fang; Yu, Su-May; Lin, Yann-Rong; Hsing, Yue-Ie Caroline

    2016-01-01

    Rice (Oryza sativa) is one of the most important crops in the world. Several rice insertional mutant libraries are publicly available for systematic analysis of gene functions. However, the tagging efficiency of these mutant resources–the relationship between genotype and phenotype–is very low. We used whole-genome sequencing to analyze a T-DNA–tagged transformant from the Taiwan Rice Insertional Mutants (TRIM) resource. The phenomics records for M0028590, one of the TRIM lines, revealed three phenotypes–wild type, large grains, and tillering dwarf–in the 12 T1 plants. Using the sequencing data for 7 plants from three generations of this specific line, we demonstrate that introgression from an indica rice variety might occur in one generation before the seed was used for callus generation and transformation of this line. In addition, the large-grain trait came from the GS3 gene of the introgressed region and the tillering dwarf phenotype came from a single nucleotide change in the D17 gene that occurred during the callus induction to regeneration of the transformant. As well, another regenerant showed completely heterozygous single-nucleotide polymorphisms across the whole genome. In addition to the known sequence changes such as T-DNA integration, single nucleotide polymorphism, insertion, deletion, chromosome rearrangement and doubling, spontaneous outcrossing occurred in the rice field may also explain some mutated traits in a tagged mutant population. Thus, the co-segregation of an integration event and the phenotype should be checked when using these mutant populations. PMID:27186981

  2. An evaluation of introgression of Atlantic coast striped bass mitochondrial DNA in a Gulf of Mexico population using formalin-preserved museum collections.

    PubMed

    Wirgin, I; Maceda, L; Stabile, J; Mesing, C

    1997-10-01

    Striped bass Morone saxatilis populations in drainages along the Gulf of Mexico coast (Gulf) were depleted in the 1950s and 1960s, probably because of anthropogenic influences. It is believed that only the Apalachicola-Chattahoochee-Flint (A-C-F) river system continually supported a naturally reproducing population of Gulf lineage. Striped bass juveniles of Atlantic coast (Atlantic) ancestry were introduced to restore population abundances in the A-C-F from the late 1960s to the mid 1970s and in many other Gulf rivers from the 1960s to the present. We previously identified mtDNA polymorphisms that were unique to approximately 60% of striped bass from the A-C-F and which confirmed the continued successful natural reproduction of striped bass of Gulf maternal ancestry within the system. However, the genetic relatedness of the extant A-C-F population to 'pure' Gulf striped bass was not addressed. In this study, we determined the frequency of a diagnostic mtDNA XbaI polymorphism in samples of 'pure' Gulf striped bass that were collected from the A-C-F prior to the introduction of Atlantic fish, that were obtained from museum collections, and that were originally preserved in formalin. PCR primers were developed that allowed for amplification of a 191-bp mtDNA fragment that contained the diagnostic XbaI restriction site. Using RFLP and direct sequence analyses of the PCR amplicons, we found no significant differences in mtDNA XbaI genotype frequencies between the archived samples and extant A-C-F samples collected over a 15-year period. This indicates that significant maternally mediated introgression of Atlantic mtDNA genomes into the A-C-F gene pool has not occurred. Additionally, we found no evidence of the unique Gulf mtDNA genotype in striped bass from extant populations in Texas, Louisiana and the Mississippi River. These results highlight the importance of the A-C-F as a repository of striped bass to restore extirpated Gulf populations and the potential use of

  3. Molecular and ecological signs of mitochondrial adaptation: consequences for introgression?

    PubMed Central

    Boratyński, Z; Melo-Ferreira, J; Alves, P C; Berto, S; Koskela, E; Pentikäinen, O T; Tarroso, P; Ylilauri, M; Mappes, T

    2014-01-01

    The evolution of the mitochondrial genome and its potential adaptive impact still generates vital debates. Even if mitochondria have a crucial functional role, as they are the main cellular energy suppliers, mitochondrial DNA (mtDNA) introgression is common in nature, introducing variation in populations upon which selection may act. Here we evaluated whether the evolution of mtDNA in a rodent species affected by mtDNA introgression is explained by neutral expectations alone. Variation in one mitochondrial and six nuclear markers in Myodes glareolus voles was examined, including populations that show mtDNA introgression from its close relative, Myodes rutilus. In addition, we modelled protein structures of the mtDNA marker (cytochrome b) and estimated the environmental envelopes of mitotypes. We found that massive mtDNA introgression occurred without any trace of introgression in the analysed nuclear genes. The results show that the native glareolus mtDNA evolved under past positive selection, suggesting that mtDNA in this system has selective relevance. The environmental models indicate that the rutilus mitotype inhabits colder and drier habitats than the glareolus one that can result from local adaptation or from the geographic context of introgression. Finally, homology models of the cytochrome b protein revealed a substitution in rutilus mtDNA in the vicinity of the catalytic fraction, suggesting that differences between mitotypes may result in functional changes. These results suggest that the evolution of mtDNA in Myodes may have functional, ecological and adaptive significance. This work opens perspective onto future experimental tests of the role of natural selection in mtDNA introgression in this system. PMID:24690754

  4. Molecular and ecological signs of mitochondrial adaptation: consequences for introgression?

    PubMed

    Boratyński, Z; Melo-Ferreira, J; Alves, P C; Berto, S; Koskela, E; Pentikäinen, O T; Tarroso, P; Ylilauri, M; Mappes, T

    2014-10-01

    The evolution of the mitochondrial genome and its potential adaptive impact still generates vital debates. Even if mitochondria have a crucial functional role, as they are the main cellular energy suppliers, mitochondrial DNA (mtDNA) introgression is common in nature, introducing variation in populations upon which selection may act. Here we evaluated whether the evolution of mtDNA in a rodent species affected by mtDNA introgression is explained by neutral expectations alone. Variation in one mitochondrial and six nuclear markers in Myodes glareolus voles was examined, including populations that show mtDNA introgression from its close relative, Myodes rutilus. In addition, we modelled protein structures of the mtDNA marker (cytochrome b) and estimated the environmental envelopes of mitotypes. We found that massive mtDNA introgression occurred without any trace of introgression in the analysed nuclear genes. The results show that the native glareolus mtDNA evolved under past positive selection, suggesting that mtDNA in this system has selective relevance. The environmental models indicate that the rutilus mitotype inhabits colder and drier habitats than the glareolus one that can result from local adaptation or from the geographic context of introgression. Finally, homology models of the cytochrome b protein revealed a substitution in rutilus mtDNA in the vicinity of the catalytic fraction, suggesting that differences between mitotypes may result in functional changes. These results suggest that the evolution of mtDNA in Myodes may have functional, ecological and adaptive significance. This work opens perspective onto future experimental tests of the role of natural selection in mtDNA introgression in this system. PMID:24690754

  5. [Detection of the introgression of genome elements of Aegilops cylindrica Host. into Triticum aestivum L. genome with ISSR-analysis].

    PubMed

    Galaev, A V; Babaiants, L T; Sivolap, Iu M

    2003-01-01

    Comparative analysis of introgressive and parental forms of wheat was carried out to reveal the sites of donor genome with new loci of resistance to fungal diseases. By ISSR-method 124 ISSR-loci were detected in the genomes of 18 individual plants of introgressive line 5/20-91; 17 of them have been related to introgressive fragments of Ae. cylindrica genome in T. aestivum. It was shown that ISSR-method is effective for detection of the variability caused by introgression of alien genetic material to T. aestivum genome. PMID:12945176

  6. Distinguishing between Incomplete Lineage Sorting and Genomic Introgressions: Complete Fixation of Allospecific Mitochondrial DNA in a Sexually Reproducing Fish (Cobitis; Teleostei), despite Clonal Reproduction of Hybrids

    PubMed Central

    Choleva, Lukas; Musilova, Zuzana; Kohoutova-Sediva, Alena; Paces, Jan; Rab, Petr; Janko, Karel

    2014-01-01

    Distinguishing between hybrid introgression and incomplete lineage sorting causing incongruence among gene trees in that they exhibit topological differences requires application of statistical approaches that are based on biologically relevant models. Such study is especially challenging in hybrid systems, where usual vectors mediating interspecific gene transfers - hybrids with Mendelian heredity - are absent or unknown. Here we study a complex of hybridizing species, which are known to produce clonal hybrids, to discover how one of the species, Cobitis tanaitica, has achieved a pattern of mito-nuclear mosaic genome over the whole geographic range. We appplied three distinct methods, including the method using solely the information on gene tree topologies, and found that the contrasting mito-nuclear signal might not have resulted from the retention of ancestral polymorphism. Instead, we found two signs of hybridization events related to C. tanaitica; one concerning nuclear gene flow and the other suggested mitochondrial capture. Interestingly, clonal inheritance (gynogenesis) of contemporary hybrids prevents genomic introgressions and non-clonal hybrids are either absent or too rare to be detected among European Cobitis. Our analyses therefore suggest that introgressive hybridizations are rather old episodes, mediated by previously existing hybrids whose inheritance was not entirely clonal. Cobitis complex thus supports the view that the type of resulting hybrids depends on a level of genomic divergence between sexual species. PMID:24971792

  7. Alienation Incident.

    ERIC Educational Resources Information Center

    Wasserman, Louis

    1979-01-01

    Critiques Marxian "cures" for alienation as discussed in Karl Marx's "Economic and Philosophical Manuscripts." Also traces the activity of a former student who joined the revolution in Cuba. Journal available from 7 Harwood Drive, Amherst, New York, 14226. (KC)

  8. The aliens inside human DNA: HERV-W/MSRV/syncytin-1 endogenous retroviruses and neurodegeneration.

    PubMed

    Dolei, Antonina; Uleri, Elena; Ibba, Gabriele; Caocci, Maurizio; Piu, Claudia; Serra, Caterina

    2015-06-01

    The human genome contains remnants of ancestral retroviruses now endogenously transmitted, called human endogenous retroviruses (HERVs). HERVs can be variably expressed, and both beneficial and detrimental effects have described. This review focuses on the MSRV and syncytin-1 HERV-W elements in relationship to neurodegeneration in view of their neuro-pathogenic and immune-pathogenic properties. Multiple sclerosis (MS) and a neurodegenerative disease (neuroAIDS) are reported in this review. In vivo studies in patients and controls for molecular epidemiology and follow-up studies are reviewed, along with in vitro cellular studies of the effects of treatments and of molecular mechanisms. HERV-W/MSRV has been repeatedly found in MS patients (in blood, spinal fluid, and brain samples), and MRSV presence/load strikingly parallels MS stages and active/remission phases, as well as therapy outcome. The DNA of MS patients has increased MSRVenv copies, while syncytin-1 copies are unchanged in controls. Presence of MSRV in the spinal fluid predicted the worst MS progression, ten years in advance. The Epstein-Barr virus (EBV) activates HERV-W/MSRV both in vitro and in vivo. With respect to neuroAIDS, the HIV transactivator of transcription (Tat) protein activates HERV-W/MSRV in monocytes/macrophages and astrocytes indirectly by interaction with TLR4 and induction of TNFa. HERV-W/MSRV can be considered a biomarker for MS behavior and therapy outcome. Regarding MS pathogenesis, we postulate the possibility for EBV of an initial trigger of future MS, years later, and for MSRV of a direct role of effector of neuropathogenesis during MS. Additionally, HERV-W/MSR/syncytin-1 activation by HIV Tat could contribute to the HIV-related neurodegeneration. PMID:26142666

  9. Alien Abductions

    NASA Astrophysics Data System (ADS)

    Nickell, Joe

    2000-03-01

    Since the beginning of the modern UFO craze in 1947, an elaborate mythology has developed concerning alleged extraterrestrial visitations. ``Flying saucer" sightings (typically involving misperceptions of such mundane phenomena as meteors and research balloons) began to be accompanied in the 1950s by reports from ``contactees," persons who claimed to have had close encounters with, even to have been transported to distant planets by, UFO occupants. By the 1960s came reports of sporadic ``abductions" which have proliferated in correlation with media interest. (Indeed, by interaction between claimants and media the portrayal of aliens has evolved from a multiplicity of types into the rather standardized big-eyed humanoid model.) While evidence of alien contact has often been faked--as by spurious photos, ``crop circles," and the notorious ``Alien Autopsy" film--few alien abduction reports appear to be hoaxes. Most seem instead to come from sincere, sane individuals. Nevertheless, not one has been authenticated, and serious investigation shows that such claims can be explained as sleep-related phenomena (notably ``waking dreams"), hypnotic confabulation, and other psychological factors. As is typical of other mythologies, the alien myth involves supernormal beings that may interact with humans, and it purports to explain the workings of the universe and humanity's place within it.

  10. Genetic and Epigenetic Alterations of Brassica nigra Introgression Lines from Somatic Hybridization: A Resource for Cauliflower Improvement.

    PubMed

    Wang, Gui-Xiang; Lv, Jing; Zhang, Jie; Han, Shuo; Zong, Mei; Guo, Ning; Zeng, Xing-Ying; Zhang, Yue-Yun; Wang, You-Ping; Liu, Fan

    2016-01-01

    Broad phenotypic variations were obtained previously in derivatives from the asymmetric somatic hybridization of cauliflower "Korso" (Brassica oleracea var. botrytis, 2n = 18, CC genome) and black mustard "G1/1" (Brassica nigra, 2n = 16, BB genome). However, the mechanisms underlying these variations were unknown. In this study, 28 putative introgression lines (ILs) were pre-selected according to a series of morphological (leaf shape and color, plant height and branching, curd features, and flower traits) and physiological (black rot/club root resistance) characters. Multi-color fluorescence in situ hybridization revealed that these plants contained 18 chromosomes derived from "Korso." Molecular marker (65 simple sequence repeats and 77 amplified fragment length polymorphisms) analysis identified the presence of "G1/1" DNA segments (average 7.5%). Additionally, DNA profiling revealed many genetic and epigenetic differences among the ILs, including sequence alterations, deletions, and variation in patterns of cytosine methylation. The frequency of fragments lost (5.1%) was higher than presence of novel bands (1.4%), and the presence of fragments specific to Brassica carinata (BBCC 2n = 34) were common (average 15.5%). Methylation-sensitive amplified polymorphism analysis indicated that methylation changes were common and that hypermethylation (12.4%) was more frequent than hypomethylation (4.8%). Our results suggested that asymmetric somatic hybridization and alien DNA introgression induced genetic and epigenetic alterations. Thus, these ILs represent an important, novel germplasm resource for cauliflower improvement that can be mined for diverse traits of interest to breeders and researchers. PMID:27625659

  11. Genetic and Epigenetic Alterations of Brassica nigra Introgression Lines from Somatic Hybridization: A Resource for Cauliflower Improvement

    PubMed Central

    Wang, Gui-xiang; Lv, Jing; Zhang, Jie; Han, Shuo; Zong, Mei; Guo, Ning; Zeng, Xing-ying; Zhang, Yue-yun; Wang, You-ping; Liu, Fan

    2016-01-01

    Broad phenotypic variations were obtained previously in derivatives from the asymmetric somatic hybridization of cauliflower “Korso” (Brassica oleracea var. botrytis, 2n = 18, CC genome) and black mustard “G1/1” (Brassica nigra, 2n = 16, BB genome). However, the mechanisms underlying these variations were unknown. In this study, 28 putative introgression lines (ILs) were pre-selected according to a series of morphological (leaf shape and color, plant height and branching, curd features, and flower traits) and physiological (black rot/club root resistance) characters. Multi-color fluorescence in situ hybridization revealed that these plants contained 18 chromosomes derived from “Korso.” Molecular marker (65 simple sequence repeats and 77 amplified fragment length polymorphisms) analysis identified the presence of “G1/1” DNA segments (average 7.5%). Additionally, DNA profiling revealed many genetic and epigenetic differences among the ILs, including sequence alterations, deletions, and variation in patterns of cytosine methylation. The frequency of fragments lost (5.1%) was higher than presence of novel bands (1.4%), and the presence of fragments specific to Brassica carinata (BBCC 2n = 34) were common (average 15.5%). Methylation-sensitive amplified polymorphism analysis indicated that methylation changes were common and that hypermethylation (12.4%) was more frequent than hypomethylation (4.8%). Our results suggested that asymmetric somatic hybridization and alien DNA introgression induced genetic and epigenetic alterations. Thus, these ILs represent an important, novel germplasm resource for cauliflower improvement that can be mined for diverse traits of interest to breeders and researchers. PMID:27625659

  12. Biased introgression of mitochondrial and nuclear genes: a comparison of diploid and haplodiploid systems.

    PubMed

    Patten, Manus M; Carioscia, Sara A; Linnen, Catherine R

    2015-10-01

    Hybridization between recently diverged species, even if infrequent, can lead to the introgression of genes from one species into another. The rates of mitochondrial and nuclear introgression often differ, with some taxa showing biases for mitochondrial introgression and others for nuclear introgression. Several hypotheses exist to explain such biases, including adaptive introgression, sex differences in dispersal rates, sex-specific prezygotic isolation and sex-specific fitness of hybrids (e.g. Haldane's rule). We derive a simple population genetic model that permits an analysis of sex-specific demographic and fitness parameters and measures the relative rates of mitochondrial and nuclear introgression between hybridizing pairs. We do this separately for diploid and haplodiploid species. For diploid taxa, we recover results consistent with previous hypotheses: an excess of one sex among the hybridizing migrants or sex-specific prezygotic isolation causes a bias for one type of marker or the other; when Haldane's rule is obeyed, we find a mitochondrial bias in XY systems and a nuclear bias in ZW systems. For haplodiploid taxa, the model reveals that owing to their unique transmission genetics, they are seemingly assured of strong mitochondrial biases in introgression rates, unlike diploid taxa, where the relative fitness of male and female hybrids can tip the bias in either direction. This heretofore overlooked aspect of hybridization in haplodiploids provides what is perhaps the most likely explanation for differential introgression of mitochondrial and nuclear markers and raises concerns about the use of mitochondrial DNA barcodes for species delimitation in these taxa. PMID:26173469

  13. Introgression and characterization of barley yellow dwarf virus resistance from Thinopyrum intermedium into wheat.

    PubMed

    Sharma, H; Ohm, H; Goulart, L; Lister, R; Appels, R; Benlhabib, O

    1995-04-01

    Wheatgrasses (species of Agropyron complex) have previously been reported to be resistant to barley yellow dwarf virus (BYDV). To introgress this resistance into wheat, Triticum aestivum x Thinopyrum (Agropyron) intermedium hybrids were advanced through a backcrossing program and reaction to BYDV, as determined by enzyme-linked immunosorbent assay (ELISA), is reported for the first time in backcross populations of wide hybrids between wheat and wheatgrasses. ELISA values revealed highly resistant to highly susceptible segregants in backcrosses. BYDV resistance was expressed in some backcross derivatives. Continued selection, based on cytology and ELISA in each generation, eliminated most of the unwanted wheatgrass chromosomes and produced self-fertile BYDV resistant wheat lines. The BYDV resistant lines with 2n = 42 had normal chromosome pairing similar to wheat, and their F1 hybrids with wheat had two univalents. DNA analyses showed that the source of alien chromatin in these BYDV resistant wheat lines is distinguishable from that in other Th. intermedium derived BYDV resistant wheat lines. Chromosome pairing and restriction fragment length polymorphism analyses indicated that the 42 chromosome resistant Purdue wheat lines are substitution lines in which chromosome 7D was replaced by a chromosome from Th. intermedium that was carrying gene(s) for BYDV resistance. PMID:18470179

  14. Asymmetric Introgression in a Spotted Salamander Hybrid Zone.

    PubMed

    Johnson, Benjamin B; White, Thomas A; Phillips, Christopher A; Zamudio, Kelly R

    2015-01-01

    Before the establishment of reproductive isolation, deeply diverged intraspecific lineages can experience complex genetic and behavioral interactions as they come into secondary contact. Divergent selective and demographic processes mediate gene flow among lineages, resulting in hybrid zones with complex biogeographic structure. Discordance in the biogeographic patterns of autosomal and maternally inherited loci provides a useful window to infer the processes mediating admixture and introgression across hybrid zones. Here, we sampled 489 genotypes across a hybrid zone between 2 phylogeographic lineages of the spotted salamander, Ambystoma maculatum, and characterize discordant patterns of nuclear and mitochondrial introgression across the contact boundary. Our results indicate asymmetric introgression of nuclear DNA beyond the contact boundary from the western to eastern lineage, with introgression of eastern mitochondrial DNA into the western lineage. We discuss alternative mechanisms for this pattern and attribute this result to neutral patterns of population expansion of the western lineage into the east in combination with female mate choice for larger-bodied western males. Our results underscore the complexity of interacting mechanisms that give rise to reproductive asymmetries in the earliest stages of the speciation process. PMID:26136297

  15. The Genetic Cost of Neanderthal Introgression.

    PubMed

    Harris, Kelley; Nielsen, Rasmus

    2016-06-01

    Approximately 2-4% of genetic material in human populations outside Africa is derived from Neanderthals who interbred with anatomically modern humans. Recent studies have shown that this Neanderthal DNA is depleted around functional genomic regions; this has been suggested to be a consequence of harmful epistatic interactions between human and Neanderthal alleles. However, using published estimates of Neanderthal inbreeding and the distribution of mutational fitness effects, we infer that Neanderthals had at least 40% lower fitness than humans on average; this increased load predicts the reduction in Neanderthal introgression around genes without the need to invoke epistasis. We also predict a residual Neanderthal mutational load in non-Africans, leading to a fitness reduction of at least 0.5%. This effect of Neanderthal admixture has been left out of previous debate on mutation load differences between Africans and non-Africans. We also show that if many deleterious mutations are recessive, the Neanderthal admixture fraction could increase over time due to the protective effect of Neanderthal haplotypes against deleterious alleles that arose recently in the human population. This might partially explain why so many organisms retain gene flow from other species and appear to derive adaptive benefits from introgression. PMID:27038113

  16. Bidirectional introgressive hybridization between Lepus capensis and Lepus yarkandensis.

    PubMed

    Wu, Yonghua; Xia, Lin; Zhang, Qian; Yang, Qisen; Meng, Xiuxiang

    2011-06-01

    Lepus capensis and Lepus yarkandensis are two well-established hare species with different habitat preferences and obvious morphological distinctions. L. capensis is common and widespread while L. yarkandensis is an endemic species with a restricted distribution in the Tarim Basin of western China. During field sampling, individuals with a distinct phenotype were found in the contact zone between the two species. To understand the origin of these unclassified individuals, we analyzed morphological and genetic data from 700 individuals including L. yarkandensis, L. capensis and the unclassified individuals. Morphological analyses of the unclassified individuals revealed that they lie between L. yarkandensis and L. capensis. Genetic analyses based on species-specific molecular markers (mitochondrial control region and SRY) showed that the unclassified populations have mtDNA and SRY genes from both L. capensis and L. yarkandensis, suggesting that the unclassified populations result from hybridization between the two species. Interestingly, many identical and/or very similar mtDNA haplotypes were shared between L. capensis populations and L. yarkandensis populations close to their contact zones, which further suggests the existence of extensive bidirectional mtDNA introgression. Similarly, we found evidence for SRY introgression, though it existed at a lower level compared to mtDNA introgression. PMID:21463697

  17. Asymmetric hybridization and introgression between pink salmon and chinook salmon in the Laurentian Great Lakes

    USGS Publications Warehouse

    Rosenfield, Jonathan A.; Todd, Thomas; Greil, Roger

    2000-01-01

    Among Pacific salmon collected in the St. Marys River, five natural hybrids of pink salmon Oncorhynchus gorbuscha and chinook salmon Oncorhynchus tshawytscha and one suspected backcross have been detected using morphologic, meristic, and color evidence. One allozyme (LDH, l-lactate dehydrogenase from muscle) and one nuclear DNA locus (growth hormone) for which species-specific fixed differences exist were analyzed to detect additional hybrids and to determine if introgression had occurred. Restriction fragment length polymorphism of mitochondrial DNA (mtDNA) was used to identify the maternal parent of each hybrid. Evidence of introgression was found among the five previously identified hybrids. All hybrid specimens had chinook salmon mtDNA, indicating that hybridization between chinook salmon and pink salmon in the St. Marys River is asymmetric and perhaps unidirectional. Ecological, physiological, and sexual selection forces may contribute to this asymmetric hybridization. Introgression between these highly differentiated species has implications for management, systematics, and conservation of Pacific salmon.

  18. Mitochondrial introgression and complex biogeographic history of the genus Picea.

    PubMed

    Ran, Jin-Hua; Shen, Ting-Ting; Liu, Wen-Juan; Wang, Pei-Pei; Wang, Xiao-Quan

    2015-12-01

    Biogeographic history of plants is much more complex in the Northern Hemisphere than in the Southern Hemisphere due to that both the Bering and the North Atlantic land bridges contributed to floristic exchanges in the Cenozoic, which led to hybridization between congeneric species from different continents. It would be interesting to know how intercontinental gene flow and introgression have affected plant phylogenetic reconstruction and biogeographic inference. In this study, we reinvestigated the phylogenetic and biogeographic history of Picea, a main component of the Northern Hemisphere forest with many species that originated from recent radiation, using two chloroplast (cp), one mitochondrial (mt) and three single-copy nuclear gene markers. The generated gene trees are topologically highly discordant and the geographically closely related species generally show a close affinity of mtDNA rather than cp- or nuclear DNA, suggesting that inter- and intra-continental gene flow and mtDNA introgression might have occurred commonly. However, all gene trees resolved Picea breweriana as the basal-most lineage, which, together with fossil evidence, supports the North American origin hypothesis for the genus. Both dispersal and vicariance have played important roles in the evolution of Picea, and the Bering Land Bridge could have mediated the "North America to Eurasia" dispersal at least two times during the Miocene and Pliocene. Our study again demonstrates the importance of applying data from three genomes for a clear understanding of evolutionary histories in the pine family. Any markers from a single genome alone will not reveal a clear picture of the phylogenetic relationships among closely related congeneric species. In particular, mtDNA markers should be cautiously used, considering that introgression of the maternally inherited mtDNA with a lower rate of gene flow (by seeds) could have occurred much more frequently than that of the paternally inherited cpDNA with

  19. Alienation, Dogmatism and Acquiescence.

    ERIC Educational Resources Information Center

    Ray, John J.

    1984-01-01

    Examined the issue of acquiescence by administering a balanced dogmatism scale and a balanced alienation scale to a random sample of Australians (N=118). Results showed that dogmatism and alienation did not correlate when acquiescence was controlled. (LLL)

  20. Gene-flow in a mosaic hybrid zone: is local introgression adaptive?

    PubMed

    Fraïsse, Christelle; Roux, Camille; Welch, John J; Bierne, Nicolas

    2014-07-01

    Genome-wide scans of genetic differentiation between hybridizing taxa can identify genome regions with unusual rates of introgression. Regions of high differentiation might represent barriers to gene flow, while regions of low differentiation might indicate adaptive introgression-the spread of selectively beneficial alleles between reproductively isolated genetic backgrounds. Here we conduct a scan for unusual patterns of differentiation in a mosaic hybrid zone between two mussel species, Mytilus edulis and M. galloprovincialis. One outlying locus, mac-1, showed a characteristic footprint of local introgression, with abnormally high frequency of edulis-derived alleles in a patch of M. galloprovincialis enclosed within the mosaic zone, but low frequencies outside of the zone. Further analysis of DNA sequences showed that almost all of the edulis allelic diversity had introgressed into the M. galloprovincialis background in this patch. We then used a variety of approaches to test the hypothesis that there had been adaptive introgression at mac-1. Simulations and model fitting with maximum-likelihood and approximate Bayesian computation approaches suggested that adaptive introgression could generate a "soft sweep," which was qualitatively consistent with our data. Although the migration rate required was high, it was compatible with the functioning of an effective barrier to gene flow as revealed by demographic inferences. As such, adaptive introgression could explain both the reduced intraspecific differentiation around mac-1 and the high diversity of introgressed alleles, although a localized change in barrier strength may also be invoked. Together, our results emphasize the need to account for the complex history of secondary contacts in interpreting outlier loci. PMID:24788603

  1. Introgression of chromosome 3Ns from Psathyrostachys huashanica into wheat specifying resistance to stripe rust.

    PubMed

    Kang, Houyang; Wang, Yi; Fedak, George; Cao, Wenguang; Zhang, Haiqin; Fan, Xing; Sha, Lina; Xu, Lili; Zheng, Youliang; Zhou, Yonghong

    2011-01-01

    Wheat stripe rust is a destructive disease in the cool and humid wheat-growing areas of the world. Finding diverse sources of stripe rust resistance is critical for increasing genetic diversity of resistance for wheat breeding programs. Stripe rust resistance was identified in the alien species Psathyrostachys huashanica, and a wheat-P. huashanica amphiploid line (PHW-SA) with stripe rust resistance was reported previously. In this study, a P. huashanica 3Ns monosomic addition line (PW11) with superior resistance to stripe rust was developed, which was derived from the cross between PHW-SA and wheat J-11. We evaluated the alien introgressions PW11-2, PW11-5 and PW11-8 which were derived from line PW11 for reaction to new Pst race CYR32, and used molecular and cytogenetic tools to characterize these lines. The introgressions were remarkably resistant to CYR32, suggesting that the resistance to stripe rust of the introgressions thus was controlled by gene(s) located on P. huashanica chromosome 3Ns. All derived lines were cytologically stable in term of meiotic chromosome behavior. Two 3Ns chromosomes of P. huashanica were detected in the disomic addition line PW11-2. Chromosomes 1B of substitution line PW11-5 had been replaced by a pair of P. huashanica 3Ns chromosomes. In PW11-8, a small terminal segment from P. huashanica chromosome arm 3NsS was translocated to the terminal region of wheat chromosomes 3BL. Thus, this translocated chromosome is designated T3BL-3NsS. These conclusions were further confirmed by SSR analyses. Two 3Ns-specific markers Xgwm181 and Xgwm161 will be useful to rapidly identify and trace the translocated fragments. These introgressions, which had significant characteristics of resistance to stripe rust, could be utilized as novel germplasms for wheat breeding. PMID:21760909

  2. Extensive Hybridization and Introgression between Melastoma candidum and M. sanguineum

    PubMed Central

    Liu, Ting; Chen, Yunyun; Chao, Lifang; Wang, Shuqiong; Wu, Wei; Dai, Seping; Wang, Feng; Fan, Qiang; Zhou, Renchao

    2014-01-01

    Natural hybridization can lead to various evolutionary outcomes in plants, including hybrid speciation and interspecific gene transfer. It can also cause taxonomic problems, especially in plant genera containing multiple species. In this study, the hybrid status of Melastoma affine, the most widespread taxon in this genus, and introgression between its putative parental species, M. candidum and M. sanguineum, were assessed on two sites, Hainan and Guangdong, using 13 SSR markers and sequences of a chloroplast intergenic spacer. Bayesian-based STRUCTURE analysis detected two most likely distinct clusters for the three taxa, and 76.0% and 73.9% of the morphologically identified individuals of M. candidum and M. sanguineum were correctly assigned, respectively. 74.5% of the M. affine individuals had a membership coefficient to either parental species between 0.1 and 0.9, suggesting admixture between M. candidum and M. sanguineum. Furthermore, NewHybrids analysis suggested that most individuals of M. affine were F2 hybrids or backcross hybrids to M. candidum, and that there was extensive introgression between M. candidum and M. sanguineum. These SSR data thus provides convincing evidence for hybrid origin of M. affine and extensive introgression between M. candidum and M. sanguineum. Chloroplast DNA results were consistent with this conclusion. Much higher hybrid frequency on the more disturbed Guangdong site suggests that human disturbance might offer suitable habitats for the survival of hybrids, a hypothesis that is in need of further testing. PMID:24797959

  3. Introgressive hybridization and latitudinal admixture clines in North Atlantic eels

    PubMed Central

    2014-01-01

    Background Hybridization, the interbreeding of diagnosably divergent species, is a major focus in evolutionary studies. Eels, both from North America and Europe migrate through the Atlantic to mate in a vast, overlapping area in the Sargasso Sea. Due to the lack of direct observation, it is unknown how these species remain reproductively isolated. The detection of inter-species hybrids in Iceland suggests on-going gene flow, but few studies to date have addressed the influence of introgression on genetic differentiation in North Atlantic eels. Results Here, we show that while mitochondrial lineages remain completely distinct on both sides of the Atlantic, limited hybridization is detectable with nuclear DNA markers. The nuclear hybridization signal peaks in the northern areas and decreases towards the southern range limits on both continents according to Bayesian assignment analyses. By simulating increasing proportions of both F1 hybrids and admixed individuals from the southern to the northern-most locations, we were able to generate highly significant isolation-by-distance patterns in both cases, reminiscent of previously published data for the European eel. Finally, fitting an isolation-with-migration model to our data supports the hypothesis of recent asymmetric introgression and refutes the alternative hypothesis of ancient polymorphism. Conclusions Fluctuating degrees of introgressive hybridization between Atlantic eel species are sufficient to explain temporally varying correlations of geographic and genetic distances reported for populations of the European eel. PMID:24674242

  4. Evidence of sexually dimorphic introgression in Pinaleno Mountain Apache trout

    USGS Publications Warehouse

    Porath, M.T.; Nielsen, J.L.

    2003-01-01

    The high-elevation headwater streams of the Pinaleno Mountains support small populations of threatened Apache trout Oncorhynchus apache that were stocked following the chemical removal of nonnative salmonids in the 1960s. A fisheries survey to assess population composition, growth, and size structure confirmed angler reports of infrequent occurrences of Oncorhynchus spp. exhibiting the external morphological characteristics of both Apache trout and rainbow trout O. mykiss. Nonlethal tissue samples were collected from 50 individuals in the headwaters of each stream. Mitochondrial DNA (mtDNA) sequencing and amplification of nuclear microsatellite loci were used to determine the levels of genetic introgression by rainbow trout in Apache trout populations at these locations. Sexually dimorphic introgression from the spawning of male rainbow trout with female Apache trout was detected using mtDNA and microsatellites. Estimates of the degree of hybridization based on three microsatellite loci were 10-88%. The use of nonlethal DNA genetic analyses can supplement information obtained from standard survey methods and be useful in assessing the relative importance of small and sensitive populations with a history of nonnative introductions.

  5. Genetic diversity enhanced by ancient introgression and secondary contact in East Pacific black mangroves.

    PubMed

    Nettel, Alejandro; Dodd, Richard S; Afzal-Rafii, Zara; Tovilla-Hernández, Cristian

    2008-06-01

    Regional distribution of genetic diversity in widespread species may be influenced by hybridization with locally restricted, closely related species. Previous studies have shown that Central American East Pacific populations of the wide-ranged Avicennia germinans, the black mangrove, harbour higher genetic diversity than the rest of its range. Genetic diversity in this region might be enhanced by introgression with the locally restricted Avicennia bicolor. We tested the hypotheses of ancient hybridization using phylogenetic analysis of the internal transcribed spacer region (ITS) of the nuclear ribosomal DNA and intergenic chloroplast DNA; we also tested for current hybridization by population level analysis of nuclear microsatellites. Our results unveiled ancient ITS introgression between a northern Pacific Central American A. germinans lineage and A. bicolor. However, microsatellite data revealed contemporary isolation between the two species. Polymorphic ITS sequences from Costa Rica and Panama are consistent with a zone of admixture between the introgressant ITS A. germinans lineage and a southern Central American lineage of A. germinans. Interspecific introgression influenced lineage diversity and divergence at the nuclear ribosomal DNA; intraspecific population differentiation and secondary contact are more likely to have enhanced regional genetic diversity in Pacific Central American populations of the widespread A. germinans. PMID:18466233

  6. Rampant historical mitochondrial genome introgression between two species of green pond frogs, Pelophylax nigromaculatus and P. plancyi

    PubMed Central

    2010-01-01

    Background Mitochondrial introgression may result in the mitochondrial genome of one species being replaced by that of another species without leaving any trace of past hybridization in its nuclear genome. Such introgression can confuse the species genealogy estimates and lead to absurd inferences of species history. We used a phylogenetic approach to explore the potential mitochondrial genome introgression event(s) between two closely related green pond frog species, Pelophylax nigromaculatus and P. plancyi. Results DNA sequence data of one mitochondrial and two nuclear genes from an extensive sampling of the two species were collected, and the genealogies of the three genes were constructed and compared. While the two nuclear genes congruently showed mutual reciprocal monophyly of both species, the mitochondrial phylogeny separated a Korean P. nigromaculatus clade, a paraphyletic central China P. plancyi assemblage, and a large well-supported introgression clade. Within the introgression clade, the mitochondrial haplotypes of the two species were mixed together. This reticulated pattern can be most parsimoniously explained by an ancient mitochondrial introgression event from P. plancyi to P. nigromaculatus that occurred at least 1.36 MYA, followed by multiple recent introgression events from P. nigromaculatus back to P. plancyi within the last 0.63 MY. The re-constitution of previously co-adapted genomes in P. plancyi may be responsible for the recent rampant introgression events. The Korean P. nigromaculatus clade likely represents the only surviving "true" mitochondrial lineage of P. nigromaculatus, and the central China P. plancyi assemblage likely represents the "original" P. plancyi mitochondrial lineage. Refugia in the Korean Peninsula and central China may have played a significant role in preserving these ancient lineages. Conclusions The majority of individuals in the two species have either introgressed (P. nigromaculatus) or reclaimed (P. plancyi

  7. Alienation and Illness.

    ERIC Educational Resources Information Center

    Kobasa, Suzanne C.

    Reviews of studies of four groups (business executives, lawyers, Army officers, and working women) which demonstrate the health-damaging effects of alienation in certain life situations show that, when under stress, members of these groups who feel alienated fall ill, medically and/or psychiatrically. Three models are described which may explain…

  8. The aliens are hiding

    NASA Astrophysics Data System (ADS)

    2015-06-01

    In reply to the physicsworld.com news story “Trail goes cold on alien hotspots, for now” (28 April, http://ow.ly/MeOpZ; see also p5), which described the results of a survey that looked for unexplained pockets of infrared radiation that could have been produced by advanced alien civilizations.

  9. Alienation from School

    ERIC Educational Resources Information Center

    Hascher, Tina; Hagenauer, Gerda

    2010-01-01

    Two studies aimed at understanding the time course of alienation from school and school factors that may influence alienation from school during early adolescence. In Study 1, 434 students from grade 5-8 participated (cross-sectional design). In Study 2, we followed 356 students from grade 6-7 (longitudinal design). The results confirm the…

  10. Alienation Attitudes and Exploratory Behavior.

    ERIC Educational Resources Information Center

    Maddi, Salvatore R.

    In order to give the psychological conception of alienation greater cogency relative to the influence of sociological alienation, research is needed that ties alienation attitudes to individual personal behavior. It was hypothesized that the stronger the alienation attitudes of people, the weaker will be their exploratory behavior. Thus,…

  11. The role of introgressive hybridization in the evolution of the Gila robusta complex (Teleostei: Cyprinidae).

    PubMed

    Gerber, A S; Tibbets, C A; Dowling, T E

    2001-10-01

    The extent and impact of introgressive hybridization was examined in the Gila robusta complex of cyprinid fishes using mitochondrial DNA (mtDNA) sequence variation. Lower Colorado River basin populations of G. robusta, G. elegans, and G. cypha exhibited distinct mtDNAs, with only limited introgression of G. elegans into G. cypha. The impact of hybridization was significant in upper Colorado River basin populations; most upper basin fishes sampled exhibited only G. cypha mtDNA haplotypes, with some individuals exhibiting mtDNA from G. elegans. The complete absence of G. robusta mtDNA, even in populations of morphologically pure G. robusta, indicates extensive introgression that predates human influence. Analysis of the geographic distribution of variation identified two distinctive G. elegans lineages; however, the small number of individuals and localities sampled precluded a comprehensive analysis. Analysis of haplotype and population networks for G. cypha mtDNAs from 15 localities revealed low divergence among haplotypes; however, significant frequency differences among populations within and among drainages were found, largely attributable to samples in the Little Colorado River region. This structure was not associated with G. cypha and G. robusta, as morphotypes from the same location are more similar than conspecific forms in other locations. This indicates that morphological and mtDNA variation are affected by different evolutionary forces in Colorado River Gila and illustrates how both hybridization and local adaptation can play important roles in evolution. PMID:11761063

  12. Introgression maintains the genetic integrity of the mating-type determining chromosome of the fungus Neurospora tetrasperma

    PubMed Central

    Corcoran, Pádraic; Anderson, Jennifer L.; Jacobson, David J.; Sun, Yu; Ni, Peixiang; Lascoux, Martin; Johannesson, Hanna

    2016-01-01

    Genome evolution is driven by a complex interplay of factors, including selection, recombination, and introgression. The regions determining sexual identity are particularly dynamic parts of eukaryotic genomes that are prone to molecular degeneration associated with suppressed recombination. In the fungus Neurospora tetrasperma, it has been proposed that this molecular degeneration is counteracted by the introgression of nondegenerated DNA from closely related species. In this study, we used comparative and population genomic analyses of 92 genomes from eight phylogenetically and reproductively isolated lineages of N. tetrasperma, and its three closest relatives, to investigate the factors shaping the evolutionary history of the genomes. We found that suppressed recombination extends across at least 6 Mbp (∼63%) of the mating-type (mat) chromosome in N. tetrasperma and is associated with decreased genetic diversity, which is likely the result primarily of selection at linked sites. Furthermore, analyses of molecular evolution revealed an increased mutational load in this region, relative to recombining regions. However, comparative genomic and phylogenetic analyses indicate that the mat chromosomes are temporarily regenerated via introgression from sister species; six of eight lineages show introgression into one of their mat chromosomes, with multiple Neurospora species acting as donors. The introgressed tracts have been fixed within lineages, suggesting that they confer an adaptive advantage in natural populations, and our analyses support the presence of selective sweeps in at least one lineage. Thus, these data strongly support the previously hypothesized role of introgression as a mechanism for the maintenance of mating-type determining chromosomal regions. PMID:26893460

  13. Retrotransposon activation followed by rapid repression in introgressed rice plants.

    PubMed

    Liu, B; Wendel, J F

    2000-10-01

    Plant retrotransposons are largely inactive during normal development, but may be activated by stresses. Both copia-like and gypsy-like retrotransposons of rice were activated by introgression of DNA from the wild species Zizania latifolia Griseb. The copy number increase was associated with cytosine methylation changes of the elements. Activity of the elements was ephemeral, as evidenced by nearly identical genomic Southern hybridization patterns among randomly chosen individuals both within and between generations for a given line, and the absence of transcripts based on Northern analysis. DNA hypermethylation, internal sequence deletion, and possibly other mechanisms are likely responsible for the rapid element repression. Implications of the retroelement dynamics on plant genome evolution are discussed. PMID:11081978

  14. Life under alien skies

    NASA Astrophysics Data System (ADS)

    Dartnell, Lewis

    2012-04-01

    As the number of confirmed extrasolar planets increases, so does the likelihood that some of them will harbour life. Lewis Dartnell describes some preliminary - but increasingly well founded - efforts to predict what alien plants and animals might look like.

  15. Discordant introgression in a rapidly expanding hybrid swarm.

    PubMed

    Ward, Jessica L; Blum, Mike J; Walters, David M; Porter, Brady A; Burkhead, Noel; Freeman, Byron

    2012-06-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta × C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization. PMID:25568058

  16. Discordant introgression in a rapidly expanding hybrid swarm

    USGS Publications Warehouse

    Ward, Jessica L.; Blum, Mike J.; Walters, David M.; Porter, Brady A.; Burkhead, Noel; Freeman, Byron

    2012-01-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta x C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization.

  17. Discordant introgression in a rapidly expanding hybrid swarm

    PubMed Central

    Ward, Jessica L; Blum, Mike J; Walters, David M; Porter, Brady A; Burkhead, Noel; Freeman, Byron

    2012-01-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta × C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization. PMID:25568058

  18. [Molecular-genetic analysis of wheat (T. aestivum L.) genome with introgression of Ae. cylindrica Host genetic elements].

    PubMed

    Galaev, A V; Sivolap, Iu M

    2005-01-01

    Wheat-aegilops hybrid plants Triticum aestivum L. (2n = 42) x Aegilops cylindrica Host (2n = 28) were investigated with using microsatellite markers. In two BC1F9 lines some genome modifications connected with losing DNA fragments of initial variety or appearing of Aegilops genome elements were detected. In some investigated hybrids new amplicons lacking in parental plants were found. Substitution of wheat chromosomes for aegilops chromosomes was not revealed. Analysis of microsatellite loci in BC2F5 plants showed stable introgression of aegilops genetic elements into wheat; elimination of some transferred aegilops DNA fragments in the course of backcrossing; decreasing size of introgressive elements after backcrossing. Introgressive lines were classified according to genome changes. PMID:16250247

  19. Genetic analysis of the T. aestivum/Ae. sharonensis introgressive lines of common wheat for resistance to powdery mildew.

    PubMed

    Vdovychenko, Zh V; Antonyuk, M Z; Ternovskaya, T K

    2005-01-01

    Results of investigation of peculiarities of common wheat hybridological analysis for a discrete character, resistance for powdery mildew, governed by the alien gene from Ae. sharonensis are present. Relation between genome structure of crossed introgressive lines and deviation of empirical ratios of segregation in F2 from theoretical, based on the assumption about monogenic inheritance of considered character is established. The approach to the quantitative count of influence of such connection on distortion of actual segregation in comparison with theoretically expected ratio is developed. PMID:16250248

  20. Introgression of Prunus species in plum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of exotic species for the most stone fruits - peach, cherry, almond and apricot - has been minimal and mostly directed at rootstock development. Within Prunus, plums have had the most extensive introgression of species. Most Japanese plums (P. salicina hybrids) are consumed as fresh fruit. Pr...

  1. An integrative approach to genomic introgression mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Near-Isogenic Lines (NILs) are valuable genetic resources for many crop species, including soybean. The development of new molecular platforms promises to accelerate the mapping of genetic introgressions in these materials. Here we compare some existing and emerging methodologies for genetic intro...

  2. Genomic contributions in livestock gene introgression programmes

    PubMed Central

    Wall, Eileen; Visscher, Peter M; Hospital, Frédéric; Woolliams, John A

    2005-01-01

    The composition of the genome after introgression of a marker gene from a donor to a recipient breed was studied using analytical and simulation methods. Theoretical predictions of proportional genomic contributions, including donor linkage drag, from ancestors used at each generation of crossing after an introgression programme agreed closely with simulated results. The obligate drag, the donor genome surrounding the target locus that cannot be removed by subsequent selection, was also studied. It was shown that the number of backcross generations and the length of the chromosome affected proportional genomic contributions to the carrier chromosomes. Population structure had no significant effect on ancestral contributions and linkage drag but it did have an effect on the obligate drag whereby larger offspring groups resulted in smaller obligate drag. The implications for an introgression programme of the number of backcross generations, the population structure and the carrier chromosome length are discussed. The equations derived describing contributions to the genome from individuals from a given generation provide a framework to predict the genomic composition of a population after the introgression of a favourable donor allele. These ancestral contributions can be assigned a value and therefore allow the prediction of genetic lag. PMID:15823237

  3. IView: Introgression library visualization and query tool

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Near-isogenic lines (NIL) are powerful genetic resources to analyze phenotypic variation and are important to map-base clone genes underlying mutations and traits. With many thousands of distinct genotypes, querying introgression libraries for lines of interest is an issue. We have created a tool ...

  4. Mining wild species elleles from introgressed genotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato (Solanum Section Lycopersicon) is composed of one cultivated (S. lycopersicum) and 12 wild species. Because the species are closely related to each other, introgression breeding has been extensive and released cultivars have been improved for many more traits using wild alleles than has any o...

  5. A New Method to Scan Genomes for Introgression in a Secondary Contact Model

    PubMed Central

    Geneva, Anthony J.; Muirhead, Christina A.; Kingan, Sarah B.; Garrigan, Daniel

    2015-01-01

    Secondary contact between divergent populations or incipient species may result in the exchange and introgression of genomic material. We develop a simple DNA sequence measure, called Gmin, which is designed to identify genomic regions experiencing introgression in a secondary contact model. Gmin is defined as the ratio of the minimum between-population number of nucleotide differences in a genomic window to the average number of between-population differences. Although it is conceptually simple, one advantage of Gmin is that it is computationally inexpensive relative to model-based methods for detecting gene flow and it scales easily to the level of whole-genome analysis. We compare the sensitivity and specificity of Gmin to those of the widely used index of population differentiation, FST, and suggest a simple statistical test for identifying genomic outliers. Extensive computer simulations demonstrate that Gmin has both greater sensitivity and specificity for detecting recent introgression than does FST. Furthermore, we find that the sensitivity of Gmin is robust with respect to both the population mutation and recombination rates. Finally, a scan of Gmin across the X chromosome of Drosophila melanogaster identifies candidate regions of introgression between sub-Saharan African and cosmopolitan populations that were previously missed by other methods. These results show that Gmin is a biologically straightforward, yet powerful, alternative to FST, as well as to more computationally intensive model-based methods for detecting gene flow. PMID:25874895

  6. Differential introgression and reorganization of retrotransposons in hybrid zones between wild wheats.

    PubMed

    Senerchia, Natacha; Felber, François; North, Béatrice; Sarr, Anouk; Guadagnuolo, Roberto; Parisod, Christian

    2016-06-01

    The maintenance of species integrity despite pervasive hybridization is ruled by the interplay between reproductive barriers. Endogenous postzygotic isolation will shape the patterns of introgression in hybrid zones, leading to variable outcomes depending on the genetic mechanism involved. Here, we analysed experimental and natural hybrid populations of Aegilops geniculata and Aegilops triuncialis to examine the genetics of species boundaries in the face of gene flow. Because long-terminal repeat retrotransposons (LTR-RTs) showing differential evolutionary trajectories are probably to affect hybrid dysgenesis and reproductive isolation between these wild wheat species, we addressed the impact of LTR-RTs in shaping introgression between them. Experimental settings involving artificial sympatry and enforced crossings quantified strong, but incomplete reproductive isolation, and highlighted asymmetrical endogenous postzygotic isolation between the two species. Natural hybrid zones located in the northern Golan Heights were analysed using plastid DNA, amplified fragment length polymorphisms (AFLP) marking random sequences, and sequence-specific amplified polymorphisms (SSAP) tracking insertions from six LTR-RT families. This analysis demonstrated asymmetrical introgression and genome reorganization. In comparison with random sequences and quiescent LTR-RTs, those LTR-RTs predicted to be activated following conflicting interactions in hybrids revealed differential introgression across the hybrid zones. As also reported for synthetic F1 hybrids, such LTR-RTs were specifically reorganized in the genomes of viable hybrids, confirming that conflicts between selfish LTR-RTs may represent key incompatibilities shaping species boundaries and fostering long-term species integrity in the face of gene flow. PMID:26678573

  7. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent residence.... An alien commuter engaged in seasonal work will be presumed to have taken up residence in the...

  8. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent residence.... An alien commuter engaged in seasonal work will be presumed to have taken up residence in the...

  9. Nuclear introgression without mitochondrial introgression in two turtle species exhibiting sex-specific trophic differentiation.

    PubMed

    Mitchell, Sarah M; Muehlbauer, Laura K; Freedberg, Steven

    2016-05-01

    Despite the presence of reproductive barriers between species, interspecific gene introgression has been documented in a range of natural systems. Comparing patterns of genetic introgression in biparental versus matrilineal markers can potentially reveal sex-specific barriers to interspecific gene flow. Hybridization has been documented in the freshwater turtles Graptemys geographica and G. pseudogeographica, whose ranges are largely sympatric. Morphological differentiation between the species is restricted to females, with female G. geographica possessing large heads and jaws compared to the narrow heads of G. pseudogeographica females. If hybrid females are morphologically intermediate, they may be less successful at exploiting parental feeding niches, thereby limiting the introgression of maternally inherited, but not biparental, molecular markers. We paired sequence data with stable isotope analysis and examined sex-specific genetic introgression and trophic differentiation in sympatric populations of G. geographica and G. pseudogeographica. We observed introgression from G. pseudogeographica into G. geographica at three nuclear loci, but not at the mitochondrial locus. Analysis of ∂(15)N and ∂(13)C was consistent with species differences in trophic positioning in females, but not males. These results suggest that ecological divergence in females may reduce the opportunity for gene flow in this system. PMID:27252833

  10. Genetic structure of Miscanthus sinensis and Miscanthus sacchariflorus in Japan indicates a gradient of bidirectional but asymmetric introgression

    PubMed Central

    Clark, Lindsay V.; Stewart, J. Ryan; Nishiwaki, Aya; Toma, Yo; Kjeldsen, Jens Bonderup; Jørgensen, Uffe; Zhao, Hua; Peng, Junhua; Yoo, Ji Hye; Heo, Kweon; Yu, Chang Yeon; Yamada, Toshihiko

    2015-01-01

    Unilateral introgression from diploids to tetraploids has been hypothesized to be an important evolutionary mechanism in plants. However, few examples have been definitively identified, perhaps because data of sufficient depth and breadth were difficult to obtain before the advent of affordable high-density genotyping. Throughout Japan, tetraploid Miscanthus sacchariflorus and diploid Miscanthus sinensis are common, and occasionally hybridize. In this study, 667 M. sinensis and 78 M. sacchariflorus genotypes from Japan were characterized using 20 704 SNPs and ten plastid microsatellites. Similarity of SNP genotypes between diploid and tetraploid M. sacchariflorus indicated that the tetraploids originated through autopolyploidy. Structure analysis indicated a gradient of introgression from diploid M. sinensis into tetraploid M. sacchariflorus throughout Japan; most tetraploids had some M. sinensis DNA. Among phenotypically M. sacchariflorus tetraploids, M. sinensis ancestry averaged 7% and ranged from 1–39%, with introgression greatest in southern Japan. Unexpectedly, rare (~1%) diploid M. sinensis individuals from northern Japan were found with 6–27% M. sacchariflorus ancestry. Population structure of M. sinensis in Japan included three groups, and was driven primarily by distance, and secondarily by geographic barriers such as mountains and straits. Miscanthus speciation is a complex and dynamic process. In contrast to limited introgression between diploid M. sacchariflorus and M. sinensis in northern China, selection for adaptation to a moderate maritime climate probably favoured cross-ploidy introgressants in southern Japan. These results will help guide the selection of Miscanthus accessions for the breeding of biomass cultivars. PMID:25618143

  11. Alien Life Imagined

    NASA Astrophysics Data System (ADS)

    Brake, Mark

    2012-11-01

    1. Kosmos: aliens in ancient Greece; 2. The world turned upside down: Copernicanism and the voyages of discovery; 3. In Newton's train: pluralism and the system of the world; 4. Extraterrestrials in the early machine age; 5. After Darwin: the war of the worlds; 6. Einstein's sky: life in the new universe; 7. Ever since SETI: astrobiology in the space age; References; Index.

  12. Aliens and atheism

    NASA Astrophysics Data System (ADS)

    Campos, Sergio; de Muynck, Willem; Virginia; Peerally, Abed; Tyler, David; Stephen

    2014-11-01

    In reply to the physicsworld.com blog post "Aliens and atheists" (2 October, http://ow.ly/CQzu4), about a survey that found that atheists are more likely than religious people to believe that life exists on other planets.

  13. Alien invasive birds.

    PubMed

    Brochier, B; Vangeluwe, D; van den Berg, T

    2010-08-01

    A bird species is regarded as alien invasive if it has been introduced, intentionally or accidentally, to a location where it did not previously occur naturally, becomes capable of establishing a breeding population without further intervention by humans, spreads and becomes a pest affecting the environment, the local biodiversity, the economy and/or society, including human health. European Starling (Sturnus vulgaris), Common Myna (Acridotheres tristis) and Red-vented Bulbul (Pycnonotus cafer) have been included on the list of '100 of the World's Worst Invasive Alien Species', a subset of the Global Invasive Species Database. The 'Delivering Alien Invasive Species Inventories for Europe' project has selected Canada Goose (Branta canadensis), Ruddy Duck (Oxyura jamaicensis), Rose-ringed Parakeet (Psittacula krameri) and Sacred Ibis (Threskiornis aethiopicus) as among 100 of the worst invasive species in Europe. For each of these alien bird species, the geographic range (native and introduced range), the introduction pathway, the general impacts and the management methods are presented. PMID:20919578

  14. Introgressive hybridization in a trophically polymorphic cichlid

    PubMed Central

    Hulsey, C Darrin; García-de-León, Francisco J

    2013-01-01

    Trophically polymorphic species could represent lineages that are rapidly diverging along an ecological axis or could phenotypically mark the collapse of species through introgressive hybridization. We investigated patterns of introgression between the trophically polymorphic cichlid fish Herichthys minckleyi and its relative H. cyanoguttatus using a combination of population genetics and species tree analyses. We first examined the distribution of mitochondrial haplotypes within the alternative H. minckleyi pharyngeal jaw morphotypes that are endemic to the small desert valley of Cuatro Ciénegas. We recovered two clusters of mitochondrial haplotypes. The first contained a number of slightly differentiated cytochrome b (cytb) haplotypes that showed some phylogeographic signal and were present in both jaw morphotypes. The other haplotype was monomorphic, highly differentiated from the other cluster, present in equal frequencies in the morphotypes, and identical to H. cyanoguttatus haplotypes found outside Cuatro Ciénegas. Then, we investigated whether H. minckleyi individuals with the H. cyanoguttatus cytb were more evolutionarily similar to H. cyanoguttatus or other H. minckleyi using a species tree analysis of 84 nuclear loci. Both H. minckleyi pharyngeal morphotypes, regardless of their cytb haplotype, were quite distinct from H. cyanoguttatus. However, hybridization could be blurring subdivision within H. minckleyi as the alternative jaw morphotypes were not genetically distinct from one another. Accounting for introgression from H. cyanoguttatus will be essential to understand the evolution of the trophically polymorphic cichlid H. minckleyi. PMID:24340193

  15. Introgressive hybridization in a trophically polymorphic cichlid.

    PubMed

    Hulsey, C Darrin; García-de-León, Francisco J

    2013-11-01

    Trophically polymorphic species could represent lineages that are rapidly diverging along an ecological axis or could phenotypically mark the collapse of species through introgressive hybridization. We investigated patterns of introgression between the trophically polymorphic cichlid fish Herichthys minckleyi and its relative H. cyanoguttatus using a combination of population genetics and species tree analyses. We first examined the distribution of mitochondrial haplotypes within the alternative H. minckleyi pharyngeal jaw morphotypes that are endemic to the small desert valley of Cuatro Ciénegas. We recovered two clusters of mitochondrial haplotypes. The first contained a number of slightly differentiated cytochrome b (cytb) haplotypes that showed some phylogeographic signal and were present in both jaw morphotypes. The other haplotype was monomorphic, highly differentiated from the other cluster, present in equal frequencies in the morphotypes, and identical to H. cyanoguttatus haplotypes found outside Cuatro Ciénegas. Then, we investigated whether H. minckleyi individuals with the H. cyanoguttatus cytb were more evolutionarily similar to H. cyanoguttatus or other H. minckleyi using a species tree analysis of 84 nuclear loci. Both H. minckleyi pharyngeal morphotypes, regardless of their cytb haplotype, were quite distinct from H. cyanoguttatus. However, hybridization could be blurring subdivision within H. minckleyi as the alternative jaw morphotypes were not genetically distinct from one another. Accounting for introgression from H. cyanoguttatus will be essential to understand the evolution of the trophically polymorphic cichlid H. minckleyi. PMID:24340193

  16. Forgetting and remembering alienation theory.

    PubMed

    Yuill, Chris

    2011-01-01

    Alienation theory has acted as the stimulus for a great deal of research and writing in the history of sociology. It has formed the basis of many sociological "classics" focused on the workplace and the experiences of workers, and has also been mobilized to chart wider social malaise and individual troubles. Alienation theory usage has, however, declined significantly since its heyday of the 1960s and 1970s. Here, the reasons why alienation theory was "forgotten" and what can be gained by "remembering" alienation theory are explored. to realize this ambition this article proceeds by (1) briefly visiting differing definitions of alienation theory, before charting its high point, and the various debates and tensions of the time, during the 1960s and 1970s; (2) analysing the reasons why alienation theory fell from grace from the 1980s onwards; (3) elaborating how and why alienation theory is still relevant for sociology and the wider social sciences today. PMID:21809508

  17. Transpositional reactivation of the Dart transposon family in rice lines derived from introgressive hybridization with Zizania latifolia

    PubMed Central

    2010-01-01

    Background It is widely recognized that interspecific hybridization may induce "genome shock", and lead to genetic and epigenetic instabilities in the resultant hybrids and/or backcrossed introgressants. A prominent component involved in the genome shock is reactivation of cryptic transposable elements (TEs) in the hybrid genome, which is often associated with alteration in the elements' epigenetic modifications like cytosine DNA methylation. We have previously reported that introgressants derived from hybridization between Oryza sativa (rice) and Zizania latifolia manifested substantial methylation re-patterning and rampant mobilization of two TEs, a copia retrotransposon Tos17 and a MITE mPing. It was not known however whether other types of TEs had also been transpositionally reactivated in these introgressants, their relevance to alteration in cytosine methylation, and their impact on expression of adjacent cellular genes. Results We document in this study that the Dart TE family was transpositionally reactivated followed by stabilization in all three studied introgressants (RZ1, RZ2 and RZ35) derived from introgressive hybridization between rice (cv. Matsumae) and Z. latifolia, while the TEs remained quiescent in the recipient rice genome. Transposon-display (TD) and sequencing verified the element's mobility and mapped the excisions and re-insertions to the rice chromosomes. Methylation-sensitive Southern blotting showed that the Dart TEs were heavily methylated along their entire length, and moderate alteration in cytosine methylation patterns occurred in the introgressants relative to their rice parental line. Real-time qRT-PCR quantification on the relative transcript abundance of six single-copy genes flanking the newly excised or inserted Dart-related TE copies indicated that whereas marked difference in the expression of all four genes in both tissues (leaf and root) were detected between the introgressants and their rice parental line under both normal

  18. Multilocus analysis of introgression between two sympatric sister species of Drosophila: Drosophila yakuba and D. santomea.

    PubMed

    Llopart, Ana; Lachaise, Daniel; Coyne, Jerry A

    2005-09-01

    Drosophila yakuba is widely distributed in sub-Saharan Africa, while D. santomea is endemic to the volcanic island of São Tomé in the Atlantic Ocean, 280 km west of Gabon. On São Tomé, D. yakuba is found mainly in open lowland forests, and D. santomea is restricted to the wet misty forests at higher elevations. At intermediate elevations, the species form a hybrid zone where hybrids occur at a frequency of approximately 1%. To determine the extent of gene flow between these species we studied polymorphism and divergence patterns in 29 regions distributed throughout the genome, including mtDNA and three genes on the Y chromosome. This multilocus approach, together with the comparison to the two allopatric species D. mauritiana and D. sechellia, allowed us to distinguish between forces that should affect all genes and forces that should act on some genes (e.g., introgression). Our results show that D. yakuba mtDNA has replaced that of D. santomea and that there is also significant introgression for two nuclear genes, yellow and salr. The majority of genes, however, has remained distinct. These two species therefore do not form a "hybrid swarm" in which much of the genome shows substantial introgression while disruptive selection maintains distinctness for only a few traits (e.g., pigmentation and male genitalia). PMID:15965264

  19. Genetic and epigenetic changes in somatic hybrid introgression lines between wheat and tall wheatgrass.

    PubMed

    Liu, Shuwei; Li, Fei; Kong, Lina; Sun, Yang; Qin, Lumin; Chen, Suiyun; Cui, Haifeng; Huang, Yinghua; Xia, Guangmin

    2015-04-01

    Broad phenotypic variations were induced in derivatives of an asymmetric somatic hybridization of bread wheat (Triticum aestivum) and tall wheatgrass (Thinopyrum ponticum Podp); however, how these variations occurred was unknown. We explored the nature of these variations by cytogenetic assays and DNA profiling techniques to characterize six genetically stable somatic introgression lines. Karyotyping results show the six lines similar to their wheat parent, but GISH analysis identified the presence of a number of short introgressed tall wheatgrass chromatin segments. DNA profiling revealed many genetic and epigenetic differences, including sequences deletions, altered regulation of gene expression, changed patterns of cytosine methylation, and the reactivation of retrotransposons. Phenotypic variations appear to result from altered repetitive sequences combined with the epigenetic regulation of gene expression and/or retrotransposon transposition. The extent of genetic and epigenetic variation due to the maintenance of parent wheat cells in tissue culture was assessed and shown to be considerably lower than had been induced in the introgression lines. Asymmetric somatic hybridization provides appropriate material to explore the nature of the genetic and epigenetic variations induced by genomic shock. PMID:25670745

  20. Genetic and Epigenetic Changes in Somatic Hybrid Introgression Lines Between Wheat and Tall Wheatgrass

    PubMed Central

    Liu, Shuwei; Li, Fei; Kong, Lina; Sun, Yang; Qin, Lumin; Chen, Suiyun; Cui, Haifeng; Huang, Yinghua; Xia, Guangmin

    2015-01-01

    Broad phenotypic variations were induced in derivatives of an asymmetric somatic hybridization of bread wheat (Triticum aestivum) and tall wheatgrass (Thinopyrum ponticum Podp); however, how these variations occurred was unknown. We explored the nature of these variations by cytogenetic assays and DNA profiling techniques to characterize six genetically stable somatic introgression lines. Karyotyping results show the six lines similar to their wheat parent, but GISH analysis identified the presence of a number of short introgressed tall wheatgrass chromatin segments. DNA profiling revealed many genetic and epigenetic differences, including sequences deletions, altered regulation of gene expression, changed patterns of cytosine methylation, and the reactivation of retrotransposons. Phenotypic variations appear to result from altered repetitive sequences combined with the epigenetic regulation of gene expression and/or retrotransposon transposition. The extent of genetic and epigenetic variation due to the maintenance of parent wheat cells in tissue culture was assessed and shown to be considerably lower than had been induced in the introgression lines. Asymmetric somatic hybridization provides appropriate material to explore the nature of the genetic and epigenetic variations induced by genomic shock. PMID:25670745

  1. 22 CFR 41.71 - Transit aliens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Transit aliens. 41.71 Section 41.71 Foreign... NATIONALITY ACT, AS AMENDED Transit Aliens § 41.71 Transit aliens. (a) Transit aliens—general. An alien is classifiable as a nonimmigrant transit alien under INA 101(a) (15) (C) if the consular officer is...

  2. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... shall be made in accordance with 8 CFR 264.5. ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent...

  3. 22 CFR 41.71 - Transit aliens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Transit aliens. 41.71 Section 41.71 Foreign... NATIONALITY ACT, AS AMENDED Transit Aliens § 41.71 Transit aliens. (a) Transit aliens—general. An alien is classifiable as a nonimmigrant transit alien under INA 101(a) (15) (C) if the consular officer is...

  4. 8 CFR 232.3 - Arriving aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Arriving aliens. 232.3 Section 232.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DETENTION OF ALIENS FOR PHYSICAL AND MENTAL EXAMINATION § 232.3 Arriving aliens. When a district director has reasonable...

  5. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  6. 8 CFR 236.13 - Ineligible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 236.13 Section 236.13 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Family Unity Program §...

  7. 22 CFR 41.71 - Transit aliens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Transit aliens. 41.71 Section 41.71 Foreign... NATIONALITY ACT, AS AMENDED Transit Aliens § 41.71 Transit aliens. (a) Transit aliens—general. An alien is classifiable as a nonimmigrant transit alien under INA 101(a) (15) (C) if the consular officer is...

  8. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  9. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... shall be made in accordance with 8 CFR 264.5. ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent...

  10. 8 CFR 236.13 - Ineligible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Ineligible aliens. 236.13 Section 236.13 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Family Unity Program §...

  11. 8 CFR 232.3 - Arriving aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Arriving aliens. 232.3 Section 232.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DETENTION OF ALIENS FOR PHYSICAL AND MENTAL EXAMINATION § 232.3 Arriving aliens. When a district director has reasonable...

  12. 8 CFR 232.3 - Arriving aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Arriving aliens. 232.3 Section 232.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DETENTION OF ALIENS FOR PHYSICAL AND MENTAL EXAMINATION § 232.3 Arriving aliens. When a district director has reasonable...

  13. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  14. 8 CFR 236.13 - Ineligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Ineligible aliens. 236.13 Section 236.13 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Family Unity Program §...

  15. 22 CFR 41.71 - Transit aliens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Transit aliens. 41.71 Section 41.71 Foreign... NATIONALITY ACT, AS AMENDED Transit Aliens § 41.71 Transit aliens. (a) Transit aliens—general. An alien is classifiable as a nonimmigrant transit alien under INA 101(a) (15) (C) if the consular officer is...

  16. 8 CFR 236.13 - Ineligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Ineligible aliens. 236.13 Section 236.13 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Family Unity Program §...

  17. 8 CFR 232.3 - Arriving aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Arriving aliens. 232.3 Section 232.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DETENTION OF ALIENS FOR PHYSICAL AND MENTAL EXAMINATION § 232.3 Arriving aliens. When a district director has reasonable...

  18. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  19. 8 CFR 232.3 - Arriving aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Arriving aliens. 232.3 Section 232.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DETENTION OF ALIENS FOR PHYSICAL AND MENTAL EXAMINATION § 232.3 Arriving aliens. When a district director has reasonable...

  20. 22 CFR 41.71 - Transit aliens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Transit aliens. 41.71 Section 41.71 Foreign... NATIONALITY ACT, AS AMENDED Transit Aliens § 41.71 Transit aliens. (a) Transit aliens—general. An alien is classifiable as a nonimmigrant transit alien under INA 101(a) (15) (C) if the consular officer is...

  1. 8 CFR 236.13 - Ineligible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Ineligible aliens. 236.13 Section 236.13 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Family Unity Program §...

  2. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... shall be made in accordance with 8 CFR 264.5. ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent...

  3. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  4. Historical introgression among the American live oaks and the comparative nature of tests for introgression.

    PubMed

    Eaton, Deren A R; Hipp, Andrew L; González-Rodríguez, Antonio; Cavender-Bares, Jeannine

    2015-10-01

    Introgressive hybridization challenges the concepts we use to define species and infer phylogenetic relationships. Methods for inferring historical introgression from the genomes of extant species, such as ABBA-BABA tests, are widely used, however, their results can be easily misinterpreted. Because these tests are inherently comparative, they are sensitive to the effects of missing data (unsampled species) and nonindependence (hierarchical relationships among species). We demonstrate this using genomic RADseq data sampled from all extant species in the American live oaks (Quercus series Virentes), a group notorious for hybridization. By considering all species and their phylogenetic relationships, we were able to distinguish true hybridizing lineages from those that falsely appear admixed. Six of seven species show evidence of admixture, often with multiple other species, but which is explained by introgression among a few related lineages occurring in close proximity. We identify the Cuban oak as the most admixed lineage and test alternative scenarios for its origin. The live oaks form a continuous ring-like distribution around the Gulf of Mexico, connected in Cuba, across which they could effectively exchange alleles. However, introgression appears highly localized, suggesting that oak species boundaries and their geographic ranges have remained relatively stable over evolutionary time. PMID:26299374

  5. Extensive introgressive hybridization within the northern oriole group (Genus Icterus) revealed by three-species isolation with migration analysis

    PubMed Central

    Jacobsen, Frode; Omland, Kevin E

    2012-01-01

    Until recently, studies of divergence and gene flow among closely-related taxa were generally limited to pairs of sister taxa. However, organisms frequently exchange genes with other non-sister taxa. The “northern oriole” group within genus Icterus exemplifies this problem. This group involves the extensively studied hybrid zone between Baltimore oriole (Icterus galbula) and Bullock's oriole (I. bullockii), an alleged hybrid zone between I. bullockii and black-backed oriole (I. abeillei), and likely mtDNA introgression between I. galbula and I. abeillei. Here, we examine the divergence population genetics of the entire northern oriole group using a multipopulation Isolation-with-Migration (IM) model. In accordance with Haldane's rule, nuclear loci introgress extensively beyond the I. galbula–I. bullockii hybrid zone, while mtDNA does not. We found no evidence of introgression between I. bullockii and I. abeillei or between I. galbula and I. abeillei when all three species were analyzed together in a three-population model. However, traditional pairwise analysis suggested some nuclear introgression from I. abeillei into I. galbula, probably reflecting genetic contributions from I. bullockii unaccounted for in a two-population model. Thus, only by including all members of this group in the analysis was it possible to rigorously estimate the level of gene flow among these three closely related species. PMID:23145328

  6. Captured by Aliens

    NASA Astrophysics Data System (ADS)

    Achenbach, Joel

    2000-03-01

    Captured by Aliens is a long and twisted voyage from science to the supernatural and back again. I hung out in Roswell, N.M., spent time with the Mars Society, met a guy who was figuring out the best way to build a spaceship to go to Alpha Centauri. I visited the set of the X-Files and talked to Mulder and Scully. One day over breakfast I was told by NASA administrator Dan Goldin, We live in a fog, man! He wants the big answers to the big questions. I spent a night in the base of a huge radio telescope in the boondocks of West Virginia, awaiting the signal from the aliens. I was hypnotized in a hotel room by someone who suspected that I'd been abducted by aliens and that this had triggered my interest in the topic. In the last months of his life, I talked to Carl Sagan, who believed that the galaxy riots with intelligent civilizations. He's my hero, for his steadfast adherence to the scientific method. What I found in all this is that the big question that needs immediate attention is not what's out THERE, but what's going on HERE, on Earth, and why we think the way we do, and how we came to be here in the first place.

  7. Resistance of Tripsacorn-introgressed maize lines to Sitophilus zeamais

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), is one of the major pests of maize worldwide. We tested one Tripsacorn-introgressed inbred maize line and 42 hybrid combinations between eleven public inbred lines and 16 different Tripsacorn-introgressed inbreds for resis...

  8. Phylogeny Estimation of the Radiation of Western North American Chipmunks (Tamias) in the Face of Introgression Using Reproductive Protein Genes

    PubMed Central

    Reid, Noah; Demboski, John R.; Sullivan, Jack

    2012-01-01

    The causes and consequences of rapid radiations are major unresolved issues in evolutionary biology. This is in part because phylogeny estimation is confounded by processes such as stochastic lineage sorting and hybridization. Because these processes are expected to be heterogeneous across the genome, comparison among marker classes may provide a means of disentangling these elements. Here we use introns from nuclear-encoded reproductive protein genes expected to be resistant to introgression to estimate the phylogeny of the western chipmunks (Tamias: subgenus: Neotamias), a rapid radiation that has experienced introgressive hybridization of mitochondrial DNA (mtDNA). We analyze the nuclear loci using coalescent-based species-tree estimation methods and concatenation to estimate a species tree and we use parametric bootstraps and coalescent simulations to differentiate between phylogenetic error, coalescent stochasticity and introgressive hybridization. Results indicate that the mtDNA gene tree reflects several introgression events that have occurred between taxa of varying levels of divergence and at different time points in the tree. T. panamintinus and T. speciosus appear to be fixed for ancient mitochondrial introgressions from T. minimus. A southern Rocky Mountains clade appears well sorted (i.e., species are largely monophyletic) at multiple nuclear loci, while five of six taxa are nonmonophyletic based on cytochrome b. Our simulations reject phylogenetic error and coalescent stochasticity as causes. The results represent an advance in our understanding of the processes at work during the radiation of Tamias and suggest that sampling reproductive-protein genes may be a viable strategy for phylogeny estimation of rapid radiations in which reproductive isolation is incomplete. However, a genome-scale survey that can statistically compare heterogeneity of genealogical process at many more loci will be necessary to test this conclusion. PMID:21878471

  9. Introgression of FHB Resistance from Alien Species-Derived Lines into Spring Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have produced and collected over 300 wheat lines derived from the crosses of wheat with wild species related to wheat. Evaluation of these lines for reaction to Fusarium head blight (FHB) identified 74 lines with resistance comparable to “Sumai 3” in two greenhouse seasons. Most of the resistan...

  10. Desperately seeking aliens

    NASA Astrophysics Data System (ADS)

    Aldiss, Brian W.

    2001-02-01

    Belief that intelligent life is commonplace in the Universe was taken for granted by scholars and scientists until well into the nineteenth century. Space travel since the late 1950s reignited the debate, which even now attracts discussion by serious, professional scientists. And although statisticians might lobby that life must surely exist somewhere in the Universe, the evolution of what we perceive as 'intelligent life' seems utterly improbable - elsewhere as well as on Earth. Can we free ourselves of our animist fantasies and accept that all alien forms of intelligent life are, and always have been, imaginary?

  11. Characteristics of successful alien plants.

    PubMed

    van Kleunen, M; Dawson, W; Maurel, N

    2015-05-01

    Herbert Baker arguably initiated the search for species characteristics determining alien plant invasion success, with his formulation of the 'ideal weed'. Today, a profusion of studies has tested a myriad of traits for their importance in explaining success of alien plants, but the multiple, not always appropriate, approaches used have led to some confusion and criticism. We argue that a greater understanding of the characteristics explaining alien plant success requires a refined approach that respects the multistage, multiscale nature of the invasion process. We present a schema of questions we can ask regarding the success of alien species, with the answering of one question in the schema being conditional on the answer of preceding questions (thus acknowledging the nested nature of invasion stages). For each question, we identify traits and attributes of species we believe are likely to be most important in explaining species success, and we make predictions as to how we expect successful aliens to differ from natives and from unsuccessful aliens in their characteristics. We organize the findings of empirical studies according to the questions in our schema that they have addressed, to assess the extent to which they support our predictions. We believe that research on plant traits of alien species has already told us a lot about why some alien species become successful after introduction. However, if we ask the right questions at the appropriate scale and use appropriate comparators, research on traits may tell us whether they are really important or not, and if so under which conditions. PMID:25421056

  12. Genomewide Variation in an Introgression Line of Rice-Zizania Revealed by Whole-Genome re-Sequencing

    PubMed Central

    Bai, Yan; Zhang, Yun-Hong; Liu, Ying; Wu, Ying; Lin, Xiu-Yun; Wen, Jia-Wei; Xu, Chun-Ming; Li, Lin-Feng; Liu, Bao

    2013-01-01

    Background Hybridization between genetically diverged organisms is known as an important avenue that drives plant genome evolution. The possible outcomes of hybridization would be the occurrences of genetic instabilities in the resultant hybrids. It remained under-investigated however whether pollination by alien pollens of a closely related but sexually "incompatible" species could evoke genomic changes and to what extent it may result in phenotypic novelties in the derived progenies. Methodology/Principal Findings In this study, we have re-sequenced the genomes of Oryza sativa ssp. japonica cv. Matsumae and one of its derived introgressant RZ35 that was obtained from an introgressive hybridization between Matsumae and Zizanialatifolia Griseb. in general, 131 millions 90 base pair (bp) paired-end reads were generated which covered 13.2 and 21.9 folds of the Matsumae and RZ35 genomes, respectively. Relative to Matsumae, a total of 41,724 homozygous single nucleotide polymorphisms (SNPs) and 17,839 homozygous insertions/deletions (indels) were identified in RZ35, of which 3,797 SNPs were nonsynonymous mutations. Furthermore, rampant mobilization of transposable elements (TEs) was found in the RZ35 genome. The results of pathogen inoculation revealed that RZ35 exhibited enhanced resistance to blast relative to Matsumae. Notably, one nonsynonymous mutation was found in the known blast resistance gene Pid3/Pi25 and real-time quantitative (q) RT-PCR analysis revealed constitutive up-regulation of its expression, suggesting both altered function and expression of Pid3/Pi25 may be responsible for the enhanced resistance to rice blast by RZ35. Conclusions/Significance Our results demonstrate that introgressive hybridization by Zizania has provoked genomewide, extensive genomic changes in the rice genome, and some of which have resulted in important phenotypic novelties. These findings suggest that introgressive hybridization by alien pollens of even a sexually incompatible

  13. Monitoring an Alien Invasion: DNA Barcoding and the Identification of Lionfish and Their Prey on Coral Reefs of the Mexican Caribbean

    PubMed Central

    Valdez-Moreno, Martha; Quintal-Lizama, Carolina; Gómez-Lozano, Ricardo; García-Rivas, María del Carmen

    2012-01-01

    Background In the Mexican Caribbean, the exotic lionfish Pterois volitans has become a species of great concern because of their predatory habits and rapid expansion onto the Mesoamerican coral reef, the second largest continuous reef system in the world. This is the first report of DNA identification of stomach contents of lionfish using the barcode of life reference database (BOLD). Methodology/Principal Findings We confirm with barcoding that only Pterois volitans is apparently present in the Mexican Caribbean. We analyzed the stomach contents of 157 specimens of P. volitans from various locations in the region. Based on DNA matches in the Barcode of Life Database (BOLD) and GenBank, we identified fishes from five orders, 14 families, 22 genera and 34 species in the stomach contents. The families with the most species represented were Gobiidae and Apogonidae. Some prey taxa are commercially important species. Seven species were new records for the Mexican Caribbean: Apogon mosavi, Coryphopterus venezuelae, C. thrix, C. tortugae, Lythrypnus minimus, Starksia langi and S. ocellata. DNA matches, as well as the presence of intact lionfish in the stomach contents, indicate some degree of cannibalism, a behavior confirmed in this species by the first time. We obtained 45 distinct crustacean prey sequences, from which only 20 taxa could be identified from the BOLD and GenBank databases. The matches were primarily to Decapoda but only a single taxon could be identified to the species level, Euphausia americana. Conclusions/Significance This technique proved to be an efficient and useful method, especially since prey species could be identified from partially-digested remains. The primary limitation is the lack of comprehensive coverage of potential prey species in the region in the BOLD and GenBank databases, especially among invertebrates. PMID:22675470

  14. Historical and current introgression in a Mesoamerican hummingbird species complex: a biogeographic perspective.

    PubMed

    Jiménez, Rosa Alicia; Ornelas, Juan Francisco

    2016-01-01

    The influence of geologic and Pleistocene glacial cycles might result in morphological and genetic complex scenarios in the biota of the Mesoamerican region. We tested whether berylline, blue-tailed and steely-blue hummingbirds, Amazilia beryllina, Amazilia cyanura and Amazilia saucerottei, show evidence of historical or current introgression as their plumage colour variation might suggest. We also analysed the role of past and present climatic events in promoting genetic introgression and species diversification. We collected mitochondrial DNA (mtDNA) sequence data and microsatellite loci scores for populations throughout the range of the three Amazilia species, as well as morphological and ecological data. Haplotype network, Bayesian phylogenetic and divergence time inference, historical demography, palaeodistribution modelling, and niche divergence tests were used to reconstruct the evolutionary history of this Amazilia species complex. An isolation-with-migration coalescent model and Bayesian assignment analysis were assessed to determine historical introgression and current genetic admixture. mtDNA haplotypes were geographically unstructured, with haplotypes from disparate areas interdispersed on a shallow tree and an unresolved haplotype network. Assignment analysis of the nuclear genome (nuDNA) supported three genetic groups with signs of genetic admixture, corresponding to: (1) A. beryllina populations located west of the Isthmus of Tehuantepec; (2) A. cyanura populations between the Isthmus of Tehuantepec and the Nicaraguan Depression (Nuclear Central America); and (3) A. saucerottei populations southeast of the Nicaraguan Depression. Gene flow and divergence time estimates, and demographic and palaeodistribution patterns suggest an evolutionary history of introgression mediated by Quaternary climatic fluctuations. High levels of gene flow were indicated by mtDNA and asymmetrical isolation-with-migration, whereas the microsatellite analyses found evidence

  15. Historical and current introgression in a Mesoamerican hummingbird species complex: a biogeographic perspective

    PubMed Central

    Jiménez, Rosa Alicia

    2016-01-01

    The influence of geologic and Pleistocene glacial cycles might result in morphological and genetic complex scenarios in the biota of the Mesoamerican region. We tested whether berylline, blue-tailed and steely-blue hummingbirds, Amazilia beryllina, Amazilia cyanura and Amazilia saucerottei, show evidence of historical or current introgression as their plumage colour variation might suggest. We also analysed the role of past and present climatic events in promoting genetic introgression and species diversification. We collected mitochondrial DNA (mtDNA) sequence data and microsatellite loci scores for populations throughout the range of the three Amazilia species, as well as morphological and ecological data. Haplotype network, Bayesian phylogenetic and divergence time inference, historical demography, palaeodistribution modelling, and niche divergence tests were used to reconstruct the evolutionary history of this Amazilia species complex. An isolation-with-migration coalescent model and Bayesian assignment analysis were assessed to determine historical introgression and current genetic admixture. mtDNA haplotypes were geographically unstructured, with haplotypes from disparate areas interdispersed on a shallow tree and an unresolved haplotype network. Assignment analysis of the nuclear genome (nuDNA) supported three genetic groups with signs of genetic admixture, corresponding to: (1) A. beryllina populations located west of the Isthmus of Tehuantepec; (2) A. cyanura populations between the Isthmus of Tehuantepec and the Nicaraguan Depression (Nuclear Central America); and (3) A. saucerottei populations southeast of the Nicaraguan Depression. Gene flow and divergence time estimates, and demographic and palaeodistribution patterns suggest an evolutionary history of introgression mediated by Quaternary climatic fluctuations. High levels of gene flow were indicated by mtDNA and asymmetrical isolation-with-migration, whereas the microsatellite analyses found evidence

  16. The complex biogeography of the plant pathogen Xylella fastidiosa: genetic evidence of introductions and Subspecific introgression in Central America.

    PubMed

    Nunney, Leonard; Ortiz, Beatriz; Russell, Stephanie A; Ruiz Sánchez, Rebeca; Stouthamer, Richard

    2014-01-01

    The bacterium Xylella fastidiosa is a plant pathogen with a history of economically damaging introductions of subspecies to regions where its other subspecies are native. Genetic evidence is presented demonstrating the introduction of two new taxa into Central America and their introgression into the native subspecies, X. fastidiosa subsp. fastidiosa. The data are from 10 genetic outliers detected by multilocus sequence typing (MLST) of isolates from Costa Rica. Six (five from oleander, one from coffee) defined a new sequence type (ST53) that carried alleles at six of the eight loci sequenced (five of the seven MLST loci) diagnostic of the South American subspecies Xylella fastidiosa subsp. pauca which causes two economically damaging plant diseases, citrus variegated chlorosis and coffee leaf scorch. The two remaining loci of ST53 carried alleles from what appears to be a new South American form of X. fastidiosa. Four isolates, classified as X. fastidiosa subsp. fastidiosa, showed a low level of introgression of non-native DNA. One grapevine isolate showed introgression of an allele from X. fastidiosa subsp. pauca while the other three (from citrus and coffee) showed introgression of an allele with similar ancestry to the alleles of unknown origin in ST53. The presence of X. fastidiosa subsp. pauca in Central America is troubling given its disease potential, and establishes another route for the introduction of this economically damaging subspecies into the US or elsewhere, a threat potentially compounded by the presence of a previously unknown form of X. fastidiosa. PMID:25379725

  17. Species introduction promotes hybridization and introgression in Coregonus: is there sign of selection against hybrids?

    PubMed

    Kahilainen, Kimmo K; Ostbye, Kjartan; Harrod, Chris; Shikano, Takahito; Malinen, Tommi; Merilä, Juha

    2011-09-01

    Species introductions are considered one of the major drivers of biodiversity loss via ecological interactions and genetic admixture with local fauna. We examined two well-recognized fish species, native whitefish (Coregonus lavaretus) and introduced vendace (Coregonus albula), as well as their morphological hybrids in a single lake to test for selection against hybrids and backcrosses in the wild. A representative random subsample of 693 individuals (27.8%) was taken from the total catch of coregonids. This subsample was examined with the aim to select c. 50 individuals of pure whitefish (n = 52), pure vendace (n = 55) and putative hybrid (n = 19) for genetic analyses. The subsequent microsatellites and mitochondrial (mt) DNA analyses provided compelling evidence of hybridization and introgression. Of the 126 fish examined, four were found to be F(1) , 14 backcrosses to whitefish and seven backcrosses to vendace. The estimates of historical gene flow suggested higher rates from introduced vendace into native whitefish than vice versa, whereas estimates of contemporary gene flow were equal. Mitochondrial introgression was skewed, with 18 backcrosses having vendace mtDNA and only three with whitefish mtDNA. Hybrids and backcrosses had intermediate morphology and niche utilization compared with parental species. No evidence of selection against hybrids or backcrosses was apparent, as both hybrid and backcross growth rates and fecundities were high. Hybrids (F(1) ) were only detected in 2 year-classes, suggesting temporal variability in mating between vendace and whitefish. However, our data show that hybrids reached sexual maturity and reproduced actively, with backcrosses recorded from six consecutive year-classes, whereas no F(2) individuals were found. The results indicate widespread introgression, as 10.8% of coregonids were estimated to be backcrosses. PMID:21831252

  18. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  19. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  20. 8 CFR 245a.32 - Ineligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Ineligible aliens. 245a.32 Section 245a.32 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS ADJUSTMENT OF STATUS TO... IMMIGRATION AND NATIONALITY ACT LIFE Act Amendments Family Unity Provisions § 245a.32 Ineligible aliens....

  1. 8 CFR 245a.32 - Ineligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Ineligible aliens. 245a.32 Section 245a.32 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS ADJUSTMENT OF STATUS TO... IMMIGRATION AND NATIONALITY ACT LIFE Act Amendments Family Unity Provisions § 245a.32 Ineligible aliens....

  2. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  3. 28 CFR 21.3 - Aliens.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Aliens. 21.3 Section 21.3 Judicial Administration DEPARTMENT OF JUSTICE WITNESS FEES § 21.3 Aliens. (a) Aliens entitled to payment of $30 per day. The following aliens are entitled to witness fees and allowances provided in § 21.4: (1)...

  4. 8 CFR 245a.32 - Ineligible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 245a.32 Section 245a.32 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS ADJUSTMENT OF STATUS TO... IMMIGRATION AND NATIONALITY ACT LIFE Act Amendments Family Unity Provisions § 245a.32 Ineligible aliens....

  5. 8 CFR 245a.32 - Ineligible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Ineligible aliens. 245a.32 Section 245a.32 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS ADJUSTMENT OF STATUS TO... IMMIGRATION AND NATIONALITY ACT LIFE Act Amendments Family Unity Provisions § 245a.32 Ineligible aliens....

  6. 28 CFR 21.3 - Aliens.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Aliens. 21.3 Section 21.3 Judicial Administration DEPARTMENT OF JUSTICE WITNESS FEES § 21.3 Aliens. (a) Aliens entitled to payment of $30 per day. The following aliens are entitled to witness fees and allowances provided in § 21.4: (1)...

  7. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  8. 28 CFR 21.3 - Aliens.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Aliens. 21.3 Section 21.3 Judicial Administration DEPARTMENT OF JUSTICE WITNESS FEES § 21.3 Aliens. (a) Aliens entitled to payment of $30 per day. The following aliens are entitled to witness fees and allowances provided in § 21.4: (1)...

  9. 28 CFR 21.3 - Aliens.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Aliens. 21.3 Section 21.3 Judicial Administration DEPARTMENT OF JUSTICE WITNESS FEES § 21.3 Aliens. (a) Aliens entitled to payment of $30 per day. The following aliens are entitled to witness fees and allowances provided in § 21.4: (1)...

  10. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  11. 28 CFR 21.3 - Aliens.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Aliens. 21.3 Section 21.3 Judicial Administration DEPARTMENT OF JUSTICE WITNESS FEES § 21.3 Aliens. (a) Aliens entitled to payment of $30 per day. The following aliens are entitled to witness fees and allowances provided in § 21.4: (1)...

  12. 8 CFR 245a.32 - Ineligible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Ineligible aliens. 245a.32 Section 245a.32 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS ADJUSTMENT OF STATUS TO... IMMIGRATION AND NATIONALITY ACT LIFE Act Amendments Family Unity Provisions § 245a.32 Ineligible aliens....

  13. Adaptive Introgression across Species Boundaries in Heliconius Butterflies

    PubMed Central

    Pardo-Diaz, Carolina; Salazar, Camilo; Baxter, Simon W.; Merot, Claire; Figueiredo-Ready, Wilsea; Joron, Mathieu; McMillan, W. Owen; Jiggins, Chris D.

    2012-01-01

    It is widely documented that hybridisation occurs between many closely related species, but the importance of introgression in adaptive evolution remains unclear, especially in animals. Here, we have examined the role of introgressive hybridisation in transferring adaptations between mimetic Heliconius butterflies, taking advantage of the recent identification of a gene regulating red wing patterns in this genus. By sequencing regions both linked and unlinked to the red colour locus, we found a region that displays an almost perfect genotype by phenotype association across four species, H. melpomene, H. cydno, H. timareta, and H. heurippa. This particular segment is located 70 kb downstream of the red colour specification gene optix, and coalescent analysis indicates repeated introgression of adaptive alleles from H. melpomene into the H. cydno species clade. Our analytical methods complement recent genome scale data for the same region and suggest adaptive introgression has a crucial role in generating adaptive wing colour diversity in this group of butterflies. PMID:22737081

  14. Alien Hand Syndrome.

    PubMed

    Hassan, Anhar; Josephs, Keith A

    2016-08-01

    Alien hand syndrome (AHS) is a rare disorder of involuntary limb movement together with a sense of loss of limb ownership. It most commonly affects the hand, but can occur in the leg. The anterior (frontal, callosal) and posterior variants are recognized, with distinguishing clinical features and anatomical lesions. Initial descriptions were attributed to stroke and neurosurgical operations, but neurodegenerative causes are now recognized as most common. Structural and functional imaging and clinical studies have implicated the supplementary motor area, pre-supplementary motor area, and their network connections in the frontal variant of AHS, and the inferior parietal lobule and connections in the posterior variant. Several theories are proposed to explain the pathophysiology. Herein, we review the literature to update advances in the understanding of the classification, pathophysiology, etiology, and treatment of AHS. PMID:27315251

  15. Crossability of Triticum urartu and Triticum monococcum Wheats, Homoeologous Recombination, and Description of a Panel of Interspecific Introgression Lines

    PubMed Central

    Fricano, Agostino; Brandolini, Andrea; Rossini, Laura; Sourdille, Pierre; Wunder, Joerg; Effgen, Sigi; Hidalgo, Alyssa; Erba, Daniela; Piffanelli, Pietro; Salamini, Francesco

    2014-01-01

    Triticum monococcum (genome Am) and T. urartu (genome Au) are diploid wheats, with the first having been domesticated in the Neolithic Era and the second being a wild species. In a germplasm collection, rare wild T. urartu lines with the presence of T. monococcum alleles were found. This stimulated our interest to develop interspecific introgression lines of T. urartu in T. monococcum, a breeding tool currently implemented in several crop species. Moreover, the experiments reported were designed to reveal the existence in nature of Am/Au intermediate forms and to clarify whether the two species are at least marginally sexually compatible. From hand-made interspecific crosses, almost-sterile F1 plants were obtained when the seed-bearing parent was T. monococcum. A high degree of fertility was, however, evident in some advanced generations, particularly when T. urartu donors were molecularly more related to T. monococcum. Analysis of the marker populations demonstrated chromosome pairing and recombination in F1 hybrid plants. Forty-six introgression lines were developed using a line of T. monococcum with several positive agronomic traits as a recurrent parent. Microsatellite markers were tested on Au and Am genomes, ordered in a T. monococcum molecular map, and used to characterize the exotic DNA fragments present in each introgression line. In a test based on 28 interspecific introgression lines, the existence of genetic variation associated with T. urartu chromosome fragments was proven for the seed content of carotenoids, lutein, β-cryptoxanthin, and zinc. The molecular state of available introgression lines is summarized. PMID:25147190

  16. Crossability of Triticum urartu and Triticum monococcum wheats, homoeologous recombination, and description of a panel of interspecific introgression lines.

    PubMed

    Fricano, Agostino; Brandolini, Andrea; Rossini, Laura; Sourdille, Pierre; Wunder, Joerg; Effgen, Sigi; Hidalgo, Alyssa; Erba, Daniela; Piffanelli, Pietro; Salamini, Francesco

    2014-10-01

    Triticum monococcum (genome A(m)) and T. urartu (genome A(u)) are diploid wheats, with the first having been domesticated in the Neolithic Era and the second being a wild species. In a germplasm collection, rare wild T. urartu lines with the presence of T. monococcum alleles were found. This stimulated our interest to develop interspecific introgression lines of T. urartu in T. monococcum, a breeding tool currently implemented in several crop species. Moreover, the experiments reported were designed to reveal the existence in nature of A(m)/A(u) intermediate forms and to clarify whether the two species are at least marginally sexually compatible. From hand-made interspecific crosses, almost-sterile F1 plants were obtained when the seed-bearing parent was T. monococcum. A high degree of fertility was, however, evident in some advanced generations, particularly when T. urartu donors were molecularly more related to T. monococcum. Analysis of the marker populations demonstrated chromosome pairing and recombination in F1 hybrid plants. Forty-six introgression lines were developed using a line of T. monococcum with several positive agronomic traits as a recurrent parent. Microsatellite markers were tested on A(u) and A(m) genomes, ordered in a T. monococcum molecular map, and used to characterize the exotic DNA fragments present in each introgression line. In a test based on 28 interspecific introgression lines, the existence of genetic variation associated with T. urartu chromosome fragments was proven for the seed content of carotenoids, lutein, β-cryptoxanthin, and zinc. The molecular state of available introgression lines is summarized. PMID:25147190

  17. Powerful methods for detecting introgressed regions from population genomic data.

    PubMed

    Rosenzweig, Benjamin K; Pease, James B; Besansky, Nora J; Hahn, Matthew W

    2016-06-01

    Understanding the types and functions of genes that are able to cross species boundaries-and those that are not-is an important step in understanding the forces maintaining species as largely independent lineages across the remainder of the genome. With large next-generation sequencing data sets we are now able to ask whether introgression has occurred across the genome, and multiple methods have been proposed to detect the signature of such events. Here, we introduce a new summary statistic that can be used to test for introgression, RNDmin , that makes use of the minimum pairwise sequence distance between two population samples relative to divergence to an outgroup. We find that our method offers a modest increase in power over other, related tests, but that all such tests have high power to detect introgressed loci when migration is recent and strong. RNDmin is robust to variation in the mutation rate, and remains reliable even when estimates of the divergence time between sister species are inaccurate. We apply RNDmin to population genomic data from the African mosquitoes Anopheles quadriannulatus and A. arabiensis, identifying three novel candidate regions for introgression. Interestingly, one of the introgressed loci is on the X chromosome, but outside of an inversion separating these two species. Our results suggest that significant, but rare, sharing of alleles is occurring between species that diverged more than 1 million years ago, and that application of these methods to additional systems are likely to reveal similar results. PMID:26945783

  18. 8 CFR 1214.2 - Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration proceedings. 1214.2 Section 1214.2 Aliens and... NONIMMIGRANT CLASSES § 1214.2 Review of alien victims of severe forms of trafficking in persons; aliens...

  19. 8 CFR 1214.2 - Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration proceedings. 1214.2 Section 1214.2 Aliens and... NONIMMIGRANT CLASSES § 1214.2 Review of alien victims of severe forms of trafficking in persons; aliens...

  20. 8 CFR 1214.2 - Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration proceedings. 1214.2 Section 1214.2 Aliens and... NONIMMIGRANT CLASSES § 1214.2 Review of alien victims of severe forms of trafficking in persons; aliens...

  1. 8 CFR 1214.2 - Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration proceedings. 1214.2 Section 1214.2 Aliens and... NONIMMIGRANT CLASSES § 1214.2 Review of alien victims of severe forms of trafficking in persons; aliens...

  2. 8 CFR 1214.2 - Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration proceedings. 1214.2 Section 1214.2 Aliens and... NONIMMIGRANT CLASSES § 1214.2 Review of alien victims of severe forms of trafficking in persons; aliens...

  3. Graffiti and "Film School" Culture: Displaying Alienation.

    ERIC Educational Resources Information Center

    Scheibel, Dean

    1994-01-01

    Examines graffiti created by students in "film school" as an organizational document. Finds themes related to alienation and the discourse that counters the sources of that alienation. Shows how the humorous communicative style of graffiti creates tension among cultural meanings that mediates between alienation and liberation. (SR)

  4. 33 CFR 125.25 - Aliens.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Aliens. 125.25 Section 125.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) WATERFRONT....25 Aliens. Alien registration records together with other papers and documents which indicated...

  5. 33 CFR 125.25 - Aliens.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Aliens. 125.25 Section 125.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) WATERFRONT....25 Aliens. Alien registration records together with other papers and documents which indicated...

  6. 43 CFR 3102.2 - Aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Aliens. 3102.2 Section 3102.2 Public Lands... INTERIOR MINERALS MANAGEMENT (3000) OIL AND GAS LEASING Qualifications of Lessees § 3102.2 Aliens. Leases or interests therein may be acquired and held by aliens only through stock ownership, holding...

  7. 33 CFR 125.25 - Aliens.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Aliens. 125.25 Section 125.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) WATERFRONT....25 Aliens. Alien registration records together with other papers and documents which indicated...

  8. 22 CFR 62.27 - Alien physicians.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Alien physicians. 62.27 Section 62.27 Foreign... Provisions § 62.27 Alien physicians. (a) Purpose. Pursuant to the Mutual Educational and Cultural Exchange... Foreign Medical Graduates must sponsor alien physicians who wish to pursue programs of graduate...

  9. 22 CFR 62.27 - Alien physicians.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Alien physicians. 62.27 Section 62.27 Foreign... Provisions § 62.27 Alien physicians. (a) Purpose. Pursuant to the Mutual Educational and Cultural Exchange... Foreign Medical Graduates must sponsor alien physicians who wish to pursue programs of graduate...

  10. 43 CFR 3102.2 - Aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Aliens. 3102.2 Section 3102.2 Public Lands... INTERIOR MINERALS MANAGEMENT (3000) OIL AND GAS LEASING Qualifications of Lessees § 3102.2 Aliens. Leases or interests therein may be acquired and held by aliens only through stock ownership, holding...

  11. 33 CFR 125.25 - Aliens.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Aliens. 125.25 Section 125.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) WATERFRONT....25 Aliens. Alien registration records together with other papers and documents which indicated...

  12. 43 CFR 3102.2 - Aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Aliens. 3102.2 Section 3102.2 Public Lands... INTERIOR MINERALS MANAGEMENT (3000) OIL AND GAS LEASING Qualifications of Lessees § 3102.2 Aliens. Leases or interests therein may be acquired and held by aliens only through stock ownership, holding...

  13. Alienation, Dogmatism, and Related Personality Characteristics.

    ERIC Educational Resources Information Center

    Sexton, Miriam E.

    1983-01-01

    Examined the relationship between alienation and dogmatism, as measured by shared personality characteristics. Scores from the Rokeach Dogmatism Scale, the Keniston Alienation Scale, the California Test of Personality, and the Omnibus Personality Inventory were obtained for 92 college freshmen. Alienation and dogmatism were positively related…

  14. 43 CFR 3102.2 - Aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Aliens. 3102.2 Section 3102.2 Public Lands... INTERIOR MINERALS MANAGEMENT (3000) OIL AND GAS LEASING Qualifications of Lessees § 3102.2 Aliens. Leases or interests therein may be acquired and held by aliens only through stock ownership, holding...

  15. 22 CFR 62.27 - Alien physicians.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Alien physicians. 62.27 Section 62.27 Foreign... Provisions § 62.27 Alien physicians. (a) Purpose. Pursuant to the Mutual Educational and Cultural Exchange... Foreign Medical Graduates must sponsor alien physicians who wish to pursue programs of graduate...

  16. 33 CFR 125.25 - Aliens.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Aliens. 125.25 Section 125.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) WATERFRONT....25 Aliens. Alien registration records together with other papers and documents which indicated...

  17. Genetic characterization of hybridization and introgression between anadromous rainbow trout (oncorhynchus mykiss irideus) and coastal cutthroat trout (o. clarki clarki)

    USGS Publications Warehouse

    Young, W.P.; Ostberg, C.O.; Keim, P.; Thorgaard, G.H.

    2001-01-01

    Interspecific hybridization represents a dynamic evolutionary phenomenon and major conservation problem in salmonid fishes. In this study we used amplified fragment length polymorphisms (AFLP) and mitochondrial DNA (mtDNA) markers to describe the extent and characterize the pattern of hybridization and introgression between coastal rainbow trout (Oncorhynchus mykiss irideus) and coastal cutthroat trout (O. clarki clarki). Hybrid individuals were initially identified using principle coordinate analysis of 133 polymorphic AFLP markers. Subsequent analysis using 23 diagnostic AFLP markers revealed the presence of F1, rainbow trout backcross, cutthroat trout backcross and later-generation hybrids. mtDNA analysis demonstrated equal numbers of F1 hybrids with rainbow and cutthroat trout mtDNA indicating reciprocal mating of the parental types. In contrast, rainbow and cutthroat trout backcross hybrids always exhibited the mtDNA from the recurrent parent, indicating a male hybrid mating with a pure female. This study illustrates the usefulness of the AFLP technique for generating large numbers of species diagnostic markers. The pattern of hybridization raises many questions concerning the existence and action of reproductive isolating mechanisms between these two species. Our findings are consistent with the hypothesis that introgression between anadromous populations of coastal rainbow and coastal cutthroat trout is limited by an environment-dependent reduction in hybrid fitness.

  18. Adaptation and possible ancient interspecies introgression in pigs identified by whole-genome sequencing.

    PubMed

    Ai, Huashui; Fang, Xiaodong; Yang, Bin; Huang, Zhiyong; Chen, Hao; Mao, Likai; Zhang, Feng; Zhang, Lu; Cui, Leilei; He, Weiming; Yang, Jie; Yao, Xiaoming; Zhou, Lisheng; Han, Lijuan; Li, Jing; Sun, Silong; Xie, Xianhua; Lai, Boxian; Su, Ying; Lu, Yao; Yang, Hui; Huang, Tao; Deng, Wenjiang; Nielsen, Rasmus; Ren, Jun; Huang, Lusheng

    2015-03-01

    Domestic pigs have evolved genetic adaptations to their local environmental conditions, such as cold and hot climates. We sequenced the genomes of 69 pigs from 15 geographically divergent locations in China and detected 41 million variants, of which 21 million were absent from the dbSNP database. In a genome-wide scan, we identified a set of loci that likely have a role in regional adaptations to high- and low-latitude environments within China. Intriguingly, we found an exceptionally large (14-Mb) region with a low recombination rate on the X chromosome that appears to have two distinct haplotypes in the high- and low-latitude populations, possibly underlying their adaptation to cold and hot environments, respectively. Surprisingly, the adaptive sweep in the high-latitude regions has acted on DNA that might have been introgressed from an extinct Sus species. Our findings provide new insights into the evolutionary history of pigs and the role of introgression in adaptation. PMID:25621459

  19. Are genes faster than crabs? Mitochondrial introgression exceeds larval dispersal during population expansion of the invasive crab Carcinus maenas.

    PubMed

    Darling, John A; Tsai, Yi-Hsin Erica; Blakeslee, April M H; Roman, Joe

    2014-10-01

    Biological invasions offer unique opportunities to investigate evolutionary dynamics at the peripheries of expanding populations. Here, we examine genetic patterns associated with admixture between two distinct invasive lineages of the European green crab, Carcinus maenas L., independently introduced to the northwest Atlantic. Previous investigations based on mitochondrial DNA sequences demonstrated that larval dispersal driven by advective currents could explain observed southward displacement of an admixture zone between the two invasions. Comparison of published mitochondrial results with new nuclear data from nine microsatellite loci, however, reveals striking discordance in their introgression patterns. Specifically, introgression of mitochondrial genomes relative to nuclear background suggests that demographic processes such as sex-biased reproductive dynamics and population size imbalances-and not solely larval dispersal-play an important role in driving the evolution of the genetic cline. In particular, the unpredicted introgression of mitochondrial alleles against the direction of mean larval dispersal in the region is consistent with recent models invoking similar demographic processes to explain movements of genes into invading populations. These observations have important implications for understanding historical shifts in C. maenas range limits, and more generally for inferences of larval dispersal based on genetic data. PMID:26064543

  20. Are genes faster than crabs? Mitochondrial introgression exceeds larval dispersal during population expansion of the invasive crab Carcinus maenas

    PubMed Central

    Darling, John A.; Tsai, Yi-Hsin Erica; Blakeslee, April M. H.; Roman, Joe

    2014-01-01

    Biological invasions offer unique opportunities to investigate evolutionary dynamics at the peripheries of expanding populations. Here, we examine genetic patterns associated with admixture between two distinct invasive lineages of the European green crab, Carcinus maenas L., independently introduced to the northwest Atlantic. Previous investigations based on mitochondrial DNA sequences demonstrated that larval dispersal driven by advective currents could explain observed southward displacement of an admixture zone between the two invasions. Comparison of published mitochondrial results with new nuclear data from nine microsatellite loci, however, reveals striking discordance in their introgression patterns. Specifically, introgression of mitochondrial genomes relative to nuclear background suggests that demographic processes such as sex-biased reproductive dynamics and population size imbalances—and not solely larval dispersal—play an important role in driving the evolution of the genetic cline. In particular, the unpredicted introgression of mitochondrial alleles against the direction of mean larval dispersal in the region is consistent with recent models invoking similar demographic processes to explain movements of genes into invading populations. These observations have important implications for understanding historical shifts in C. maenas range limits, and more generally for inferences of larval dispersal based on genetic data. PMID:26064543

  1. ALIENS IN WESTERN STREAM ECOSYSTEMS

    EPA Science Inventory

    The USEPA's Environmental Monitoring and Assessment Program conducted a five year probability sample of permanent mapped streams in 12 western US states. The study design enables us to determine the extent of selected riparian invasive plants, alien aquatic vertebrates, and some ...

  2. The Mexican "Illegal Alien" Commute.

    ERIC Educational Resources Information Center

    Decker, Phil

    1986-01-01

    A photo report of the following three treks by illegal aliens across the border from Mexico to work in Arizona reveals the dangers and disappointments the migrants are exposed to: (1) a "carpool" from Southern Mexico; (2) a train ride from Sinaloa; and (3) a 40-mile hike through the Arizona desert. (PS)

  3. The Creative Use of Alienation.

    ERIC Educational Resources Information Center

    Herrick, James E.

    The process of becoming a world citizen requires, as a first step, personal alienation from the cultural values and social arrangements of nation-states that stand in the way of such an effort. Three interrelated propositions underlie this thesis. First, prevailing cultural values and social arrangements severely limit opportunities for people to…

  4. Introgressive hybridization as a promoter of genome reshuffling in natural homoploid fish hybrids (Cyprinidae, Leuciscinae)

    PubMed Central

    Pereira, C S A; Aboim, M A; Ráb, P; Collares-Pereira, M J

    2014-01-01

    Understanding the mechanisms underlying diversification and speciation by introgressive hybridization is currently one of the major challenges in evolutionary biology. Here, the analysis of hybridization between two pairs of Iberian Leuciscinae provided new data on independent hybrid zones involving Achondrostoma oligolepis (AOL) and Pseudochondrostoma duriense (PDU), and confirmed the occurrence of hybrids between AOL and Pseudochondrostoma polylepis (PPO). A multilevel survey combining morphological, genetic and cytogenomic markers on a vast population screening successfully sorted the selected fishes as admixed. Results were similar in both AOL × PDU and AOL × PPO systems. Overall, hybrid morphotypes, cytogenomic data and genetic profiling indicated preferential backcrossing and suggested AOL as a major genomic contributor. Moreover, results implied AOL as more permissive to introgression than PDU or PPO. Although PDU- and PPO-like individuals appeared more resilient to genome modifications, AOL appeared to be more involved and affected by the ongoing hybridization events, as chromosomal translocations were only found in AOL-like individuals. All hybrids analysed evidenced extensive ribosomal DNA (rDNA) polymorphism that was not found in parental species, but usually seen falling within the range of possible parental combinations. Yet, transgressive phenotypes that cannot be explained by normal recombination, including more rDNA clusters than expected or the occurrence of syntenic rDNAs, were also detected. Present results proved rapid genomic evolution providing the genetic novelty for species to persist. In addition, although the ultimate consequences of such apparently extensive and recurrent events remain unknown, modern genome-wide methodologies are of great promise towards answering questions concerning the causes, dynamics and impacts of hybridization. PMID:24220087

  5. Reintroduction of a Homocysteine Level-Associated Allele into East Asians by Neanderthal Introgression.

    PubMed

    Hu, Ya; Ding, Qiliang; He, Yungang; Xu, Shuhua; Jin, Li

    2015-12-01

    In this study, we present an analysis of Neanderthal introgression at the dipeptidase 1 gene, DPEP1. A Neanderthal origin for the putative introgressive haplotypes was demonstrated using an established three-step approach. This introgression was under positive natural selection, reached a frequency of >50%, and introduced a homocysteine level- and pigmentation-associated allele (rs460879-T) into East Asians. However, the same allele was also found in non-East Asians, but not from Neanderthal introgression. It is likely that rs460879-T was lost in East Asians and was reintroduced subsequently through Neanderthal introgression. Our findings suggest that Neanderthal introgression could reintroduce an important previously existing allele into populations where the allele had been lost. This study sheds new light on understanding the contribution of Neanderthal introgression to the adaptation of non-Africans. PMID:26392408

  6. A Visualization and Query Tool for Introgression Libraries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Near isogenic lines are powerful resources to analyze phenotypic variation and are important in efforts to map-base clone genes underlying mutants and traits. With many thousands of distinct genotypes, querying introgression libraries for lines of interest is an issue. To make it more tractable, we ...

  7. Quantifying time-inhomogeneous stochastic introgression processes with hazard rates.

    PubMed

    Ghosh, Atiyo; Serra, Maria Conceição; Haccou, Patsy

    2012-06-01

    Introgression is the permanent incorporation of genes from one population into another through hybridization and backcrossing. It is currently of particular concern as a possible mechanism for the spread of modified crop genes to wild populations. The hazard rate is the probability per time unit that such an escape takes place, given that it has not happened before. It is a quantitative measure of introgression risk that takes the stochastic elements inherent in introgression processes into account. We present a methodology to calculate the hazard rate for situations with time-varying gene flow from a crop to a large recipient wild population. As an illustration, several types of time-inhomogeneity are examined, including deterministic periodicity as well as random variation. Furthermore, we examine the effects of an extended fitness bottleneck of hybrids and backcrosses in combination with time-varying gene flow. It is found that bottlenecks decrease the hazard rate, but also slow down and delay its changes in reaction to changes in gene flow. Furthermore, we find that random variation in gene flow generates a lower hazard rate than analogous deterministic variation. We discuss the implications of our findings for crop management and introgression risk assessment. PMID:22178309

  8. Searching for Alien Life Having Unearthly Biochemistry

    NASA Technical Reports Server (NTRS)

    Jones, Harry

    2003-01-01

    The search for alien life in the solar system should include exploring unearth-like environments for life having an unearthly biochemistry. We expect alien life to conform to the same basic chemical and ecological constraints as terrestrial life, since inorganic chemistry and the laws of ecosystems appear to be universal. Astrobiologists usually assume alien life will use familiar terrestrial biochemistry and therefore hope to find alien life by searching near water or by supplying hydrocarbons. The assumption that alien life is likely to be based on carbon and water is traditional and plausible. It justifies high priority for missions to search for alien life on Mars and Europa, but it unduly restricts the search for alien life. Terrestrial carbon-water biochemistry is not possible on most of the bodies of our solar system, but all alien life is not necessarily based on terrestrial biochemistry. If alien life has a separate origin from Earth life, and if can survive in an environment extremely different from Earth's, then alien life may have unearthly biochemistry. There may be other solvents than water that support alien life and other elements than carbon that form complex life enabling chain molecules. Rather than making the exploration-restricting assumption that all life requires carbon, water, and terrestrial biochemistry, we should make the exploration-friendly assumption that indigenous, environmentally adapted, alien life forms might flourish using unearthly biochemistry in many places in the solar system. Alien life might be found wherever there is free energy and a physical/chemical system capable of using that energy to build living structures. Alien life may be discovered by the detection of some general non-equilibrium chemistry rather than of terrestrial biochemistry. We should explore all the potential abodes of life in the solar system, including those where life based on terrestrial biochemistry can not exist.

  9. Hybridization between alien species Rumex obtusifolius and closely related native vulnerable species R. longifolius in a mountain tourist destination

    PubMed Central

    Takahashi, Koichi; Hanyu, Masaaki

    2015-01-01

    Alien species expand their distribution by transportation network development. Hybridization between alien species Rumex obtusifolius and closely related native vulnerable species R. longifolius was examined in a mountain tourist destination in central Japan. The three taxa were morphologically identified in the field. Stem height and leaf area were greater in R. longifolius than R. obtusifolius; hybrids were intermediate between the two Rumex species. R. longifolius and the hybrids grew mainly in wet land and the river tributary; R. obtusifolius grew mainly at the roadside and in meadows. Hybrid germination rates of pollen and seeds were much lower than for the two Rumex species. Clustering analysis showed the three taxa each formed a cluster. Most hybrids were F1 generation; the possibility was low of introgression into the two Rumex species by backcross. This study clarified that (1) hybridization occurred between R. obtusifolius and R. longifolius because they occurred together in a small area, but grew in different water habitat conditions, and (2) hybridization was mostly F1 generation because hybrid pollen and seed fertility was low. However, we need caution about introgression into R. longifolius by R. obtusifolius in this area because of the slight possibility of F2 generation and backcrosses. PMID:26354180

  10. Hybridization between alien species Rumex obtusifolius and closely related native vulnerable species R. longifolius in a mountain tourist destination.

    PubMed

    Takahashi, Koichi; Hanyu, Masaaki

    2015-01-01

    Alien species expand their distribution by transportation network development. Hybridization between alien species Rumex obtusifolius and closely related native vulnerable species R. longifolius was examined in a mountain tourist destination in central Japan. The three taxa were morphologically identified in the field. Stem height and leaf area were greater in R. longifolius than R. obtusifolius; hybrids were intermediate between the two Rumex species. R. longifolius and the hybrids grew mainly in wet land and the river tributary; R. obtusifolius grew mainly at the roadside and in meadows. Hybrid germination rates of pollen and seeds were much lower than for the two Rumex species. Clustering analysis showed the three taxa each formed a cluster. Most hybrids were F1 generation; the possibility was low of introgression into the two Rumex species by backcross. This study clarified that (1) hybridization occurred between R. obtusifolius and R. longifolius because they occurred together in a small area, but grew in different water habitat conditions, and (2) hybridization was mostly F1 generation because hybrid pollen and seed fertility was low. However, we need caution about introgression into R. longifolius by R. obtusifolius in this area because of the slight possibility of F2 generation and backcrosses. PMID:26354180

  11. Introgressive hybridization: brown bears as vectors for polar bear alleles.

    PubMed

    Hailer, Frank

    2015-03-01

    The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male-biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture-free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach. PMID:25775930

  12. 22 CFR 42.22 - Returning resident aliens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at...

  13. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED...

  14. 22 CFR 42.22 - Returning resident aliens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at...

  15. 22 CFR 42.22 - Returning resident aliens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at...

  16. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED...

  17. 22 CFR 42.22 - Returning resident aliens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at...

  18. 22 CFR 42.22 - Returning resident aliens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at...

  19. Introgressive Hybridization and the Evolution of Lake-Adapted Catostomid Fishes

    PubMed Central

    Dowling, Thomas E.; Markle, Douglas F.; Tranah, Greg J.; Carson, Evan W.; Wagman, David W.; May, Bernard P.

    2016-01-01

    Hybridization has been identified as a significant factor in the evolution of plants as groups of interbreeding species retain their phenotypic integrity despite gene exchange among forms. Recent studies have identified similar interactions in animals; however, the role of hybridization in the evolution of animals has been contested. Here we examine patterns of gene flow among four species of catostomid fishes from the Klamath and Rogue rivers using molecular and morphological traits. Catostomus rimiculus from the Rogue and Klamath basins represent a monophyletic group for nuclear and morphological traits; however, the Klamath form shares mtDNA lineages with other Klamath Basin species (C. snyderi, Chasmistes brevirostris, Deltistes luxatus). Within other Klamath Basin taxa, D. luxatus was largely fixed for alternate nuclear alleles relative to C. rimiculus, while Ch. brevirostris and C. snyderi exhibited a mixture of these alleles. Deltistes luxatus was the only Klamath Basin species that exhibited consistent covariation of nuclear and mitochondrial traits and was the primary source of mismatched mtDNA in Ch. brevirostris and C. snyderi, suggesting asymmetrical introgression into the latter species. In Upper Klamath Lake, D. luxatus spawning was more likely to overlap spatially and temporally with C. snyderi and Ch. brevirostris than either of those two with each other. The latter two species could not be distinguished with any molecular markers but were morphologically diagnosable in Upper Klamath Lake, where they were largely spatially and temporally segregated during spawning. We examine parallel evolution and syngameon hypotheses and conclude that observed patterns are most easily explained by introgressive hybridization among Klamath Basin catostomids. PMID:26959681

  20. Introgressive Hybridization and the Evolution of Lake-Adapted Catostomid Fishes.

    PubMed

    Dowling, Thomas E; Markle, Douglas F; Tranah, Greg J; Carson, Evan W; Wagman, David W; May, Bernard P

    2016-01-01

    Hybridization has been identified as a significant factor in the evolution of plants as groups of interbreeding species retain their phenotypic integrity despite gene exchange among forms. Recent studies have identified similar interactions in animals; however, the role of hybridization in the evolution of animals has been contested. Here we examine patterns of gene flow among four species of catostomid fishes from the Klamath and Rogue rivers using molecular and morphological traits. Catostomus rimiculus from the Rogue and Klamath basins represent a monophyletic group for nuclear and morphological traits; however, the Klamath form shares mtDNA lineages with other Klamath Basin species (C. snyderi, Chasmistes brevirostris, Deltistes luxatus). Within other Klamath Basin taxa, D. luxatus was largely fixed for alternate nuclear alleles relative to C. rimiculus, while Ch. brevirostris and C. snyderi exhibited a mixture of these alleles. Deltistes luxatus was the only Klamath Basin species that exhibited consistent covariation of nuclear and mitochondrial traits and was the primary source of mismatched mtDNA in Ch. brevirostris and C. snyderi, suggesting asymmetrical introgression into the latter species. In Upper Klamath Lake, D. luxatus spawning was more likely to overlap spatially and temporally with C. snyderi and Ch. brevirostris than either of those two with each other. The latter two species could not be distinguished with any molecular markers but were morphologically diagnosable in Upper Klamath Lake, where they were largely spatially and temporally segregated during spawning. We examine parallel evolution and syngameon hypotheses and conclude that observed patterns are most easily explained by introgressive hybridization among Klamath Basin catostomids. PMID:26959681

  1. Population structure of honey bees in the Carpathian Basin (Hungary) confirms introgression from surrounding subspecies.

    PubMed

    Péntek-Zakar, Erika; Oleksa, Andrzej; Borowik, Tomasz; Kusza, Szilvia

    2015-12-01

    Carniolan honey bees (Apis mellifera carnica) are considered as an indigenous subspecies in Hungary adapted to most of the ecological and climatic conditions in this area. However, during the last decades Hungarian beekeepers have recognized morphological signs of the Italian honey bee (Apis mellifera ligustica). As the natural distribution of the honey bee subspecies can be affected by the importation of honey bee queens or by natural gene flow, we aimed at determining the genetic structure and characteristics of the local honey bee population using molecular markers. All together, 48 Hungarian and 84 foreign (Italian, Polish, Spanish, Liberian) pupae and/or workers were used for mitochondrial DNA analysis. Additionally, 53 sequences corresponding to 10 subspecies and the Buckfast hybrid were downloaded from GenBank. For the nuclear analysis, 236 Hungarian and 106 foreign honey bees were genotyped using nine microsatellites. Heterozygosity values, population-specific alleles, FST values, principal coordinate analysis, assignment tests, structure analysis, and dendrograms were calculated. Haplotype and nucleotide diversity values showed moderate values. We found that one haplotype (H9) was dominant in Hungary. The presence of the black honey bee (Apis mellifera mellifera) was negligible, but a few individuals resembling other subspecies were identified. We proved that the Hungarian honey bee population is nearly homogeneous but also demonstrated introgression from the foreign subspecies. Both mitochondrial DNA and microsatellite analyses corroborated the observations of the beekeepers. Molecular analyses suggested that Carniolan honey bee in Hungary is slightly affected by Italian and black honey bee introgression. Genetic differences were detected between Polish and Hungarian Carniolan honey bee populations, suggesting the existence of at least two different gene pools within A. m. carnica. PMID:27069597

  2. Evolution of Trypanosoma cruzi: clarifying hybridisations, mitochondrial introgressions and phylogenetic relationships between major lineages

    PubMed Central

    Tomasini, Nicolás; Diosque, Patricio

    2015-01-01

    Several different models of Trypanosoma cruzi evolution have been proposed. These models suggest that scarce events of genetic exchange occurred during the evolutionary history of this parasite. In addition, the debate has focused on the existence of one or two hybridisation events during the evolution of T. cruzi lineages. Here, we reviewed the literature and analysed available sequence data to clarify the phylogenetic relationships among these different lineages. We observed that TcI, TcIII and TcIV form a monophyletic group and that TcIII and TcIV are not, as previously suggested, TcI-TcII hybrids. Particularly, TcI and TcIII are sister groups that diverged around the same time that a widely distributed TcIV split into two clades (TcIVS and TcIVN). In addition, we collected evidence that TcIII received TcIVS kDNA by introgression on several occasions. Different demographic hypotheses (surfing and asymmetrical introgression) may explain the origin and expansion of the TcIII group. Considering these hypotheses, genetic exchange should have been relatively frequent between TcIII and TcIVS in the geographic area in which their distributions overlapped. In addition, our results support the hypothesis that two independent hybridisation events gave rise to TcV and TcVI. Consequently, TcIVS kDNA was first transferred to TcIII and later to TcV and TcVI in TcII/TcIII hybridisation events. PMID:25807469

  3. Genomewide introgressive hybridization patterns in wild Atlantic salmon influenced by inadvertent gene flow from hatchery releases.

    PubMed

    Ozerov, M Y; Gross, R; Bruneaux, M; Vähä, J-P; Burimski, O; Pukk, L; Vasemägi, A

    2016-03-01

    Many salmonid fish populations are threatened by genetic homogenization, primarily due to introgressive hybridization with hatchery-reared conspecifics. By applying genomewide analysis using two molecular marker types (1986 SNPs and 17 microsatellites), we assessed the genetic impacts of inadvertent gene flow via straying from hatchery releases on wild populations of Atlantic salmon in the Gulf of Finland, Baltic Sea, over 16 years (1996-2012). Both microsatellites and SNPs revealed congruent population genetic structuring, indicating that introgression changed the genetic make-up of wild populations by increasing genetic diversity and reducing genetic divergence. However, the degree of genetic introgression varied among studied populations, being higher in the eastern part and lower in the western part of Estonia, which most likely reflects the history of past stocking activities. Using kernel smoothing and permutation testing, we detected considerable heterogeneity in introgression patterns across the genome, with a large number of regions exhibiting nonrandom introgression widely dispersed across the genome. We also observed substantial variation in nonrandom introgression patterns within populations, as the majority of genomic regions showing elevated or reduced introgression were not consistently detected among temporal samples. This suggests that recombination, selection and stochastic processes may contribute to complex nonrandom introgression patterns. Our results suggest that (i) some genomic regions in Atlantic salmon are more vulnerable to introgressive hybridization, while others show greater resistance to unidirectional gene flow; and (ii) the hybridization of previously separated populations leads to complex and dynamic nonrandom introgression patterns that most likely have functional consequences for indigenous populations. PMID:26840557

  4. [A case of parental alienation].

    PubMed

    Menz, Wolfgang

    2014-01-01

    The clinical term "Parental Alienation Syndrome" (PAS) was introduced in 1984 by Richard Gardner, an American psychiatrist. Gardner described PAS and its symptoms, as a personality disorder, which appears chiefly in connection to child custody disputes wherein a child turns suddenly and massively against the non-custodial parent without reasonable grounds for doing so. This action by the child is a result of the custodial parent's emotionally abusive attempts to incite the child against the non-custodial parent.Where the child's rejection is based on some real past experience, there is not PAS. PAS only occurs as a result of the custodial parent's actions. Despite intensive effort, PAS was not included in the new DSM-V. In this case, a particularly impressive case history of parental alienation is described and discussed. PMID:24464865

  5. Alien liquid detector and control

    SciTech Connect

    Potter, B.M.

    1980-09-02

    An alien liquid detector employs a monitoring element and an energizing circuit for maintaining the temperature of the monitoring element substantially above ambient temperature. For this purpose an electronic circit controls a flow of heating current to the monitoring element. The presence of an alien liquid is detected by sensing a predetermined change in heating current flow to the monitoring element, e.g., to distinguish between water and oil. In preferred embodiments the monitoring element is a thermistor whose resistance is compared with a reference resistance and heating current through the thermistor is controlled in accordance with the difference. In one embodiment a bridge circuit senses the resistance difference; the difference may be sensed by an operational amplifier arrangement. Features of the invention include positioning the monitoring element at the surface of water, slightly immersed, so that the power required to maintain the thermistor temperature substantially above ambient temperature serves to detect presence of oil pollution at the surface.

  6. Source-sink estimates of genetic introgression show influence of hatchery strays on wild chum salmon populations in Prince William Sound, Alaska.

    PubMed

    Jasper, James R; Habicht, Christopher; Moffitt, Steve; Brenner, Rich; Marsh, Jennifer; Lewis, Bert; Creelman Fox, Elisabeth; Grauvogel, Zac; Rogers Olive, Serena D; Grant, W Stewart

    2013-01-01

    The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus keta) in Prince William Sound (PWS), Alaska, with 135 single nucleotide polymorphism (SNP) markers. Historical population structure was inferred from the analysis of DNA from fish scales, which had been archived since the late 1960's for several populations in PWS. Parallel analyses with microsatellites and a test based on Hardy-Weinberg proportions showed that about 50% of the fish-scale DNA was cross-contaminated with DNA from other fish. These samples were removed from the analysis. We used a novel application of the classical source-sink model to compare SNP allele frequencies in these archived fish-scales (1964-1982) with frequencies in contemporary samples (2008-2010) and found a temporal shift toward hatchery allele frequencies in some wild populations. Other populations showed markedly less introgression, despite moderate amounts of hatchery straying. The extent of introgression may reflect similarities in spawning time and life-history traits between hatchery and wild fish, or the degree that hybrids return to a natal spawning area. The source-sink model is a powerful means of detecting low levels of introgression over several generations. PMID:24349150

  7. Asymmetrical alien hands in corticobasal degeneration.

    PubMed

    Fitzgerald, David B; Drago, Valeria; Jeong, Yong; Chang, Yu-Ling; White, Keith D; Heilman, Kenneth M

    2007-03-15

    There are several forms of alien limb, but alien limb in corticobasal degeneration (CBD) is not well understood. We studied a patient with CBD who demonstrated two different types of alien limb. With his right hand he demonstrated a tactile avoidance response with levitation. With his left hand, he demonstrated continuous tactile pursuit of the examiner's hand ("tactile mitgehen"). Mitgehen is often associated with frontal dysfunction, but avoidance response and levitation are often associated with parietal dysfunction. PMID:17230447

  8. Index of Alien Impact: A method for evaluating potential ecological impact of alien plant species

    EPA Science Inventory

    Alien plant species are stressors to ecosystems and indicators of reduced ecosystem integrity. The magnitude of the stress reflects not only the quantity of aliens present, but also the quality of their interactions with native ecosystems. We develop an Index of Alien Impact (IAI...

  9. Reproductive isolation and introgression between sympatric Mimulus species.

    PubMed

    Kenney, Amanda M; Sweigart, Andrea L

    2016-06-01

    Incompletely isolated species provide an opportunity to investigate the genetic mechanisms and evolutionary forces that maintain distinct species in the face of ongoing gene flow. Here, we use field surveys and reduced representation sequencing to characterize the patterns of reproductive isolation, admixture and genomic divergence between populations of the outcrossing wildflower Mimulus guttatus and selfing M. nasutus. Focusing on a single site where these two species have come into secondary contact, we find that phenological isolation is strong, although incomplete, and is likely driven by divergence in response to photoperiod. In contrast to previous field studies, which have suggested that F1 -hybrid formation might be rare, we discover patterns of genomic variation consistent with ongoing introgression. Strikingly, admixed individuals vary continuously from highly admixed to nearly pure M. guttatus, demonstrating ongoing hybridization and asymmetric introgression from M. nasutus into M. guttatus. Patterns of admixture and divergence across the genome show that levels of introgression are more variable than expected by chance. Some genomic regions show a reduced introgression, including one region that overlaps a critical photoperiod QTL, whereas other regions show elevated levels of interspecific gene flow. In addition, we observe a genome-wide negative relationship between absolute divergence and the local recombination rate, potentially indicating natural selection against M. nasutus ancestry in M. guttatus genetic backgrounds. Together, our results suggest that Mimulus speciation is both ongoing and dynamic and that a combination of divergence in phenology and mating system, as well as selection against interspecific alleles, likely maintains these sympatric species. PMID:27038381

  10. Chromosomal Location and Comparative Genomics Analysis of Powdery Mildew Resistance Gene Pm51 in a Putative Wheat-Thinopyrum ponticum Introgression Line

    PubMed Central

    Zhang, Xiaojun; Li, Xin; Guo, Huijuan; Gong, Wenping; Jia, Juqing; Qiao, Linyi; Ren, Yongkang; Yang, Zujun; Chang, Zhijian

    2014-01-01

    Powdery mildew (PM) is a very destructive disease of wheat (Triticum aestivum L.). Wheat-Thinopyrum ponticum introgression line CH7086 was shown to possess powdery mildew resistance possibly originating from Th. ponticum. Genomic in situ hybridization and molecular characterization of the alien introgression failed to identify alien chromatin. To study the genetics of resistance, CH7086 was crossed with susceptible genotypes. Segregation in F2 populations and F2:3 lines tested with Chinese Bgt race E09 under controlled conditions indicated that CH7086 carries a single dominant gene for powdery mildew resistance. Fourteen SSR and EST-PCR markers linked with the locus were identified. The genetic distances between the locus and the two flanking markers were 1.5 and 3.2 cM, respectively. Based on the locations of the markers by nullisomic-tetrasomic and deletion lines of ‘Chinese Spring’, the resistance gene was located in deletion bin 2BL-0.89-1.00. Conserved orthologous marker analysis indicated that the genomic region flanking the resistance gene has a high level of collinearity to that of rice chromosome 4 and Brachypodium chromosome 5. Both resistance specificities and tests of allelism suggested the resistance gene in CH7086 was different from previously reported powdery mildew resistance genes on 2BL, and the gene was provisionally designated PmCH86. Molecular analysis of PmCH86 compared with other genes for resistance to Bgt in the 2BL-0.89-1.00 region suggested that PmCH86 may be a new PM resistance gene, and it was therefore designated as Pm51. The closely linked flanking markers could be useful in exploiting this putative wheat-Thinopyrum translocation line for rapid transfer of Pm51 to wheat breeding programs. PMID:25415194

  11. Admixture mapping identifies introgressed genomic regions in North American canids.

    PubMed

    vonHoldt, Bridgett M; Kays, Roland; Pollinger, John P; Wayne, Robert K

    2016-06-01

    Hybrid zones typically contain novel gene combinations that can be tested by natural selection in a unique genetic context. Parental haplotypes that increase fitness can introgress beyond the hybrid zone, into the range of parental species. We used the Affymetrix canine SNP genotyping array to identify genomic regions tagged by multiple ancestry informative markers that are more frequent in an admixed population than expected. We surveyed a hybrid zone formed in the last 100 years as coyotes expanded their range into eastern North America. Concomitant with expansion, coyotes hybridized with wolves and some populations became more wolflike, such that coyotes in the northeast have the largest body size of any coyote population. Using a set of 3102 ancestry informative markers, we identified 60 differentially introgressed regions in 44 canines across this admixture zone. These regions are characterized by an excess of exogenous ancestry and, in northeastern coyotes, are enriched for genes affecting body size and skeletal proportions. Further, introgressed wolf-derived alleles have penetrated into Southern US coyote populations. Because no wolves currently exist in this area, these alleles are unlikely to have originated from recent hybridization. Instead, they probably originated from intraspecific gene flow or ancient admixture. We show that grey wolf and coyote admixture has far-reaching effects and, in addition to phenotypically transforming admixed populations, allows for the differential movement of alleles from different parental species to be tested in new genomic backgrounds. PMID:27106273

  12. Hybridization and introgression in two ecologically dissimilar Fundulus hybrid zones.

    PubMed

    Schaefer, Jacob; Duvernell, David; Campbell, Dave Cooper

    2016-05-01

    Hybridization and introgression appear more common in rapidly evolving groups, suggesting an important role in the evolutionary process. Detailed studies of how extrinsic or intrinsic forces regulate hybridization and introgression have the potential for broadening our understanding of mechanisms generating diversity. Species in the Fundulus notatus species complex have broad overlapping ranges and occur in replicated hybrid zones along predictable stream gradients. Typical hybrid zone structure has Fundulus olivaceus in headwaters, F. notatus downstream, and hybrid zones near confluences or abrupt shifts in habitat. Rarely, the typical upstream-downstream orientation is reversed raising questions as to how hybrid zones are formed and maintained. We used next-generation sequencing data to study hybridization and introgression in hybrid zones in neighboring drainages that differ in orientation (typical and reversed). We predicted extrinsic forces linked to stream gradients would result in noticeable differences between the two. Contrary to predictions, the data indicate the hybrid zones are remarkably similar. We used individual-based simulations to explore the potential role of intrinsic and extrinsic forces in generating and maintaining typical and reversed hybrid zones. Simulation results were consistent with reversed hybrid zones being formed from stochastic processes combined with strong intrinsic forces and weak extrinsic forces. PMID:27062071

  13. Genetic and phenotypic consequences of introgression between humans and Neanderthals.

    PubMed

    Wills, Christopher

    2011-01-01

    Strong evidence for introgression of Neanderthal genes into parts of the modern human gene pool has recently emerged. The evidence indicates that some populations of modern humans have received infusions of genes from two different groups of Neanderthals. One of these Neanderthal groups lived in the Middle East and Central Europe and the other group (the Denisovans) is known to have lived in Central Asia and was probably more widespread. This review examines two questions. First, how were these introgressions detected and what does the genetic evidence tell us about their nature and extent? We will see that an unknown but possibly large fraction of the entire Neanderthal gene complement may have survived in modern humans. Even though each modern European and Asian carries only a few percent of genes that can be traced back to Neanderthals, different individuals carry different subgroups of these introgressed genes. Second, what is the likelihood that this Neanderthal genetic legacy has had phenotypic effects on modern humans? We examine evidence for and against the possibility that some of the surviving fragments of Neanderthal genomes have been preserved by natural selection, and we explore the ways in which more evidence bearing on this question will become available in the future. PMID:22099691

  14. Influence of Introgression and Geological Processes on Phylogenetic Relationships of Western North American Mountain Suckers (Pantosteus, Catostomidae)

    PubMed Central

    Unmack, Peter J.; Dowling, Thomas E.; Laitinen, Nina J.; Secor, Carol L.; Mayden, Richard L.; Shiozawa, Dennis K.; Smith, Gerald R.

    2014-01-01

    Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data with morphological and paleontological data for proposed species of Pantosteus, (2) tests hypotheses of their monophyly, (3) uses these data for phylogenetic inferences of sister-group relationships, and (4) estimates timing of divergence events of identified lineages. Using 8055 base pairs from mitochondrial DNA protein coding genes, Pantosteus and Catostomus are reciprocally monophyletic, in contrast with morphological data. The only exception to a monophyletic Pantosteus is P. columbianus whose mtDNA is closely aligned with C. tahoensis because of introgression. Within Pantosteus, several species have deep genetic divergences among allopatric sister lineages, several of which are diagnosed and elevated to species, bringing the total diversity in the group to 11 species. Conflicting molecular and morphological data may be resolved when patterns of divergence are shown to be correlated with sympatry and evidence of introgression. PMID:24619087

  15. Introgression Between Cultivars and Wild Populations of Momordica charantia L. (Cucurbitaceae) in Taiwan

    PubMed Central

    Liao, Pei-Chun; Tsai, Chi-Chu; Chou, Chang-Hung; Chiang, Yu-Chung

    2012-01-01

    The landrace strains of Momordica charantia are widely cultivated vegetables throughout the tropics and subtropics, but not in Taiwan, a continental island in Southeast Asia, until a few hundred years ago. In contrast, the related wild populations with smaller fruit sizes are native to Taiwan. Because of the introduction of cultivars for agricultural purposes, these two accessions currently exhibit a sympatric or parapatric distribution in Taiwan. In this study, the cultivars and wild samples from Taiwan, India, and Korea were collected for testing of their hybridization and evolutionary patterns. The cpDNA marker showed a clear distinction between accessions of cultivars and wild populations of Taiwan and a long divergence time. In contrast, an analysis of eight selectively neutral nuclear microsatellite loci did not reveal a difference between the genetic structures of these two accessions. A relatively short divergence time and frequent but asymmetric gene flows were estimated based on the isolation-with-migration model. Historical and current introgression from cultivars to wild populations of Taiwan was also inferred using MIGRATE-n and BayesAss analyses. Our results showed that these two accessions shared abundant common ancestral polymorphisms, and the timing of the divergence and colonization of the Taiwanese wild populations is consistent with the geohistory of the Taiwan Strait land bridge of the Last Glacial Maximum (LGM). Long-term and recurrent introgression between accessions indicated the asymmetric capacity to receive foreign genes from other accessions. The modern introduction of cultivars of M. charantia during the colonization of Taiwan by the Han Chinese ethnic group enhanced the rate of gene replacement in the native populations and resulted in the loss of native genes. PMID:22754378

  16. Possibilities of direct introgression from Brassica napus to B. juncea and indirect introgression from B. napus to related Brassicaceae through B. juncea

    PubMed Central

    Tsuda, Mai; Ohsawa, Ryo; Tabei, Yutaka

    2014-01-01

    The impact of genetically modified canola (Brassica napus) on biodiversity has been examined since its initial stage of commercialization. Various research groups have extensively investigated crossability and introgression among species of Brassicaceae. B. rapa and B. juncea are ranked first and second as the recipients of cross-pollination and introgression from B. napus, respectively. Crossability between B. napus and B. rapa has been examined, specifically in terms of introgression from B. napus to B. rapa, which is mainly considered a weed in America and European countries. On the other hand, knowledge on introgression from B. napus to B. juncea is insufficient, although B. juncea is recognized as the main Brassicaceae weed species in Asia. It is therefore essential to gather information regarding the direct introgression of B. napus into B. juncea and indirect introgression of B. napus into other species of Brassicaceae through B. juncea to evaluate the influence of genetically modified canola on biodiversity. We review information on crossability and introgression between B. juncea and other related Brassicaseae in this report. PMID:24987292

  17. Possibilities of direct introgression from Brassica napus to B. juncea and indirect introgression from B. napus to related Brassicaceae through B. juncea.

    PubMed

    Tsuda, Mai; Ohsawa, Ryo; Tabei, Yutaka

    2014-05-01

    The impact of genetically modified canola (Brassica napus) on biodiversity has been examined since its initial stage of commercialization. Various research groups have extensively investigated crossability and introgression among species of Brassicaceae. B. rapa and B. juncea are ranked first and second as the recipients of cross-pollination and introgression from B. napus, respectively. Crossability between B. napus and B. rapa has been examined, specifically in terms of introgression from B. napus to B. rapa, which is mainly considered a weed in America and European countries. On the other hand, knowledge on introgression from B. napus to B. juncea is insufficient, although B. juncea is recognized as the main Brassicaceae weed species in Asia. It is therefore essential to gather information regarding the direct introgression of B. napus into B. juncea and indirect introgression of B. napus into other species of Brassicaceae through B. juncea to evaluate the influence of genetically modified canola on biodiversity. We review information on crossability and introgression between B. juncea and other related Brassicaseae in this report. PMID:24987292

  18. Alienation and Expectation in American Political Culture.

    ERIC Educational Resources Information Center

    Ranney, Austin

    The concept of political alienation in American culture is examined in light of evidence gathered by social scientists. Political alienation is interpreted to include a wide variety of attitudes and behaviors such as cynicism, outraged idealism, apathy, violent protest, powerlessness, and revolutionary zeal. To minimize conceptual ambiguities of…

  19. Alienating Students: Marxist Theory in Action

    ERIC Educational Resources Information Center

    Thiele, Megan; Pan, Yung-Yi Dian; Molina, Devin

    2016-01-01

    Karl Marx's revolutionary call, "Workers of the World Unite," resonates with many in today's society. This article describes and assesses an easily reproducible classroom activity that simulates both alienating, and perhaps more importantly, non-alienating states of production as described by Marx. This hands-on learning activity gives…

  20. Alienation and Use of the Mass Media.

    ERIC Educational Resources Information Center

    Pietila, Veikko

    Several studies in media viewing have examined the hypothesis that alienation correlates with the consumption of escape-type content from the mass media. In order to interpret this result, alienation was considered as a process beginning with difficiulties in situation definitions. It was assumed in this study that heavy information of the mass…

  1. Alienation, Mass Society and Mass Culture.

    ERIC Educational Resources Information Center

    Dam, Hari N.

    This monograph examines the nature of alienation in mass society and mass culture. Conceptually based on the "Gemeinschaft-Gesellschaft" paradigm of sociologist Ferdinand Tonnies, discussion traces the concept of alienation as it appears in the philosophies of Hegel, Marx, Kierkegaard, Sartre, and others. Dwight Macdonald's "A Theory of Mass…

  2. Alienation in the Barrio: Eastern New Mexico.

    ERIC Educational Resources Information Center

    Donnelly, Jerry D.

    Preliminary to a larger research project on Mexican American attitudes, this report focused on the extent to which feelings of alienation are present in the barrios of 5 eastern New Mexico population centers. The feelings of alienation were analyzed by the degree of powerlessness, normlessness, self-estrangement, and isolation expressed or…

  3. Revisiting the role of introgression vs shared ancestral polymorphisms as key processes shaping genetic diversity in the recently separated sibling species of the Anopheles gambiae complex.

    PubMed

    Donnelly, M J; Pinto, J; Girod, R; Besansky, N J; Lehmann, T

    2004-02-01

    The role of interspecific hybridisation in the evolution of pest species is poorly understood. In mosquito disease vectors this is of particular importance due to the evolution of insecticide resistance and the proposed release of transgenic strains that are refractory to the malaria parasite. In this study, we apply population genetic methods in a novel manner to determine whether mitochondrial DNA sequences have introgressed between the closely related African malaria vectors Anopheles gambiae and A. arabiensis. Our results suggest that speciation was geologically recent and ancestral haplotypes at the ND5 locus are retained in both species. In addition, comparing haplotype frequencies in allopatric and sympatric populations, suggest locale specific unidirectional introgression of mitochondria from A. arabiensis into A. gambiae. PMID:14666125

  4. Alienation, dogmatism, and related personality characteristics.

    PubMed

    Sexton, M E

    1983-01-01

    Examined the relationship between alienation and dogmatism, as measured by shared personality characteristics. Scores from the Rokeach Dogmatism Scale, the Keniston Alienation Scale, the California Test of Personality, and the Omnibus Personality Inventory were obtained for a sample of 92 college freshmen. Alienation and dogmatism were found to be positively related concepts. The factors that best predicted alienation from dogmatic responses were intolerance expressed for opposing beliefs and compulsivity in the belief system. Alienation and dogmatism also were found to be associated with several commonly held personality traits, which center around anxiety, low self-esteem, and social estrangement manifested in feelings of hostility, aggression, loneliness, rejection, and isolation. These results were discussed and compared to previous research that explored the two concepts separately. PMID:6826758

  5. Weak Population Structure in European Roe Deer (Capreolus capreolus) and Evidence of Introgressive Hybridization with Siberian Roe Deer (C. pygargus) in Northeastern Poland

    PubMed Central

    Olano-Marin, Juanita; Plis, Kamila; Sönnichsen, Leif; Borowik, Tomasz; Niedziałkowska, Magdalena; Jędrzejewska, Bogumiła

    2014-01-01

    We investigated contemporary and historical influences on the pattern of genetic diversity of European roe deer (Capreolus capreolus). The study was conducted in northeastern Poland, a zone where vast areas of primeval forests are conserved and where the European roe deer was never driven to extinction. A total of 319 unique samples collected in three sampling areas were genotyped at 16 microsatellites and one fragment (610 bp) of mitochondrial DNA (mtDNA) control region. Genetic diversity was high, and a low degree of genetic differentiation among sampling areas was observed with both microsatellites and mtDNA. No evidence of genetic differentiation between roe deer inhabiting open fields and forested areas was found, indicating that the ability of the species to exploit these contrasting environments might be the result of its phenotypic plasticity. Half of the studied individuals carried an mtDNA haplotype that did not belong to C. capreolus, but to a related species that does not occur naturally in the area, the Siberian roe deer (C. pygargus). No differentiation between individuals with Siberian and European mtDNA haplotypes was detected at microsatellite loci. Introgression of mtDNA of Siberian roe deer into the genome of European roe deer has recently been detected in eastern Europe. Such introgression might be caused by human-mediated translocations of Siberian roe deer within the range of European roe deer or by natural hybridization between these species in the past. PMID:25271423

  6. A haplotype at STAT2 Introgressed from neanderthals and serves as a candidate of positive selection in Papua New Guinea.

    PubMed

    Mendez, Fernando L; Watkins, Joseph C; Hammer, Michael F

    2012-08-10

    Signals of archaic admixture have been identified through comparisons of the draft Neanderthal and Denisova genomes with those of living humans. Studies of individual loci contributing to these genome-wide average signals are required for characterization of the introgression process and investigation of whether archaic variants conferred an adaptive advantage to the ancestors of contemporary human populations. However, no definitive case of adaptive introgression has yet been described. Here we provide a DNA sequence analysis of the innate immune gene STAT2 and show that a haplotype carried by many Eurasians (but not sub-Saharan Africans) has a sequence that closely matches that of the Neanderthal STAT2. This haplotype, referred to as N, was discovered through a resequencing survey of the entire coding region of STAT2 in a global sample of 90 individuals. Analyses of publicly available complete genome sequence data show that haplotype N shares a recent common ancestor with the Neanderthal sequence (~80 thousand years ago) and is found throughout Eurasia at an average frequency of ~5%. Interestingly, N is found in Melanesian populations at ~10-fold higher frequency (~54%) than in Eurasian populations. A neutrality test that controls for demography rejects the hypothesis that a variant of N rose to high frequency in Melanesia by genetic drift alone. Although we are not able to pinpoint the precise target of positive selection, we identify nonsynonymous mutations in ERBB3, ESYT1, and STAT2-all of which are part of the same 250 kb introgressive haplotype-as good candidates. PMID:22883142

  7. Molecular marker-assisted alien gene introgression of Sr39 for wheat stem rust resistance derived from Aegilops speltoides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In wheat (Triticum aestivum L.), stem rust resistance gene Sr39, derived from Aegilops speltoides, is highly effective against multiple stem rust races including Ug99. However, the gene has not been used in wheat breeding because it is located on a large 2S chromosomal segment in the current transl...

  8. The Rp3 disease resistance gene of maize: mapping and characterization of introgressed alleles.

    PubMed

    Sanz-Alferez, S; Richter, T E; Hulbert, S H; Bennetzen, J L

    1995-07-01

    The Rp3 locus of maize conditions race-specific resistance to a fungal rust pathogen, Puccinia sorghi. Both morphological and DNA markers were employed to characterize alleles of Rp3 and to accurately position Rp3 on the maize genetic map. DNA marker polymorphisms distinctive to each Rp3 allele were identified, allowing the identification of specific Rp3 alleles in cases where rust races that differentiate particular alleles are not available. In a population of 427 progeny, Rp3 and Rg1 were found to be completely linked, while Lg3 was approximately 3 cM proximal on the long arm of chromosome 3. In this same population, 12 RFLP markers were mapped relative to Rp3; the closest markers were UMC102 (about 1cM distal to Rp1) and NPI114 (1-2 cM proximal). These and additional DNA probes were used to characterize the nature and extent of flanking DNA that was carried along when six different Rp3 alleles were backcrossed into a single background. Depending upon the allele investigated, a minimum of 2-10cM of polymorphic DNA flanking the Rp3 locus was retained through the introgression process. In addition, many of the probes that map near Rp3 were found to detect an additional fragment in the Rp3 region, indicating that portions of this chromosomal segment have been tendemly duplicated. The materials and results generated will permit marker-assisted entry of Rp3 into different maize backgrounds and lay the foundation for the eventual map-based cloning of Rp3. PMID:24169663

  9. 31 CFR 515.335 - Permanent resident alien.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States....

  10. 45 CFR 233.52 - Overpayment to aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Overpayment to aliens. 233.52 Section 233.52... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall...

  11. 26 CFR 1.6654-6 - Nonresident alien individuals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 13 2012-04-01 2012-04-01 false Nonresident alien individuals. 1.6654-6 Section... Penalties § 1.6654-6 Nonresident alien individuals. (a) In general. A nonresident alien individual is... the gross income of a nonresident alien individual is such as to require making a payment of...

  12. 22 CFR 40.91 - Certain aliens previously removed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a...

  13. 47 CFR 90.115 - Foreign government and alien eligibility.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Foreign government and alien eligibility. 90... government and alien eligibility. (a) No station authorization in the radio services governed by this part....9(c) of this chapter) if such entity is: (1) An alien or the representative of any alien; (2)...

  14. 8 CFR 274a.3 - Continuing employment of unauthorized aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Continuing employment of unauthorized aliens. 274a.3 Section 274a.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employer Requirements § 274a.3 Continuing employment...

  15. 22 CFR 40.92 - Aliens unlawfully present.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Aliens unlawfully present. 40.92 Section 40.92... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.92 Aliens unlawfully present. (a) 3-year bar. An alien described in INA 212(a)(9)(B)(i)(I) shall be ineligible for...

  16. 45 CFR 233.52 - Overpayment to aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 2 2013-10-01 2012-10-01 true Overpayment to aliens. 233.52 Section 233.52 Public... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall...

  17. 8 CFR 1240.38 - Fingerprinting of excluded aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Fingerprinting of excluded aliens. 1240.38 Section 1240.38 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Exclusion...

  18. 45 CFR 1626.7 - Verification of eligible alien status.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the...

  19. 45 CFR 1626.5 - Alien status and eligibility.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Alien status and eligibility. 1626.5 Section 1626... RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.5 Alien status and eligibility. Subject to all other... may provide legal assistance to an alien who is present in the United States and who is within one...

  20. 31 CFR 515.335 - Permanent resident alien.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States....

  1. 26 CFR 1.871-3 - Residence of alien seamen.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Residence of alien seamen. 1.871-3 Section 1.871... (CONTINUED) INCOME TAXES Nonresident Aliens and Foreign Corporations § 1.871-3 Residence of alien seamen. In order to determine whether an alien seaman is a resident of the United States for purposes of the...

  2. 45 CFR 1626.5 - Alien status and eligibility.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Alien status and eligibility. 1626.5 Section 1626... RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.5 Alien status and eligibility. Subject to all other... may provide legal assistance to an alien who is present in the United States and who is within one...

  3. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...(c) of 8 CFR chapter I. (b) Service custody and cost of maintenance. An alien confined because of... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT...

  4. 26 CFR 1.6654-6 - Nonresident alien individuals.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 13 2013-04-01 2013-04-01 false Nonresident alien individuals. 1.6654-6 Section... Penalties § 1.6654-6 Nonresident alien individuals. (a) In general. A nonresident alien individual is... the gross income of a nonresident alien individual is such as to require making a payment of...

  5. 8 CFR 1240.38 - Fingerprinting of excluded aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Fingerprinting of excluded aliens. 1240.38 Section 1240.38 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Exclusion...

  6. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...(c) of 8 CFR chapter I. (b) Service custody and cost of maintenance. An alien confined because of... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT...

  7. 26 CFR 1.871-3 - Residence of alien seamen.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 9 2013-04-01 2013-04-01 false Residence of alien seamen. 1.871-3 Section 1.871... (CONTINUED) INCOME TAXES (CONTINUED) Nonresident Aliens and Foreign Corporations § 1.871-3 Residence of alien seamen. In order to determine whether an alien seaman is a resident of the United States for purposes...

  8. 22 CFR 40.92 - Aliens unlawfully present.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens unlawfully present. 40.92 Section 40.92... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.92 Aliens unlawfully present. (a) 3-year bar. An alien described in INA 212(a)(9)(B)(i)(I) shall be ineligible for...

  9. 26 CFR 1.871-3 - Residence of alien seamen.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 9 2012-04-01 2012-04-01 false Residence of alien seamen. 1.871-3 Section 1.871... (CONTINUED) INCOME TAXES (CONTINUED) Nonresident Aliens and Foreign Corporations § 1.871-3 Residence of alien seamen. In order to determine whether an alien seaman is a resident of the United States for purposes...

  10. 22 CFR 40.91 - Certain aliens previously removed.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a...

  11. 8 CFR 274a.3 - Continuing employment of unauthorized aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Continuing employment of unauthorized aliens. 274a.3 Section 274a.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employer Requirements § 274a.3 Continuing employment...

  12. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...(c) of 8 CFR chapter I. (b) Service custody and cost of maintenance. An alien confined because of... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT...

  13. 26 CFR 1.6654-6 - Nonresident alien individuals.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Nonresident alien individuals. 1.6654-6 Section....6654-6 Nonresident alien individuals. (a) In general. A nonresident alien individual is required to... gross income of a nonresident alien individual is such as to require making a payment of...

  14. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...(c) of 8 CFR chapter I. (b) Service custody and cost of maintenance. An alien confined because of... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT...

  15. 26 CFR 1.6654-6 - Nonresident alien individuals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 13 2011-04-01 2011-04-01 false Nonresident alien individuals. 1.6654-6 Section... Penalties § 1.6654-6 Nonresident alien individuals. (a) In general. A nonresident alien individual is... the gross income of a nonresident alien individual is such as to require making a payment of...

  16. 45 CFR 1626.5 - Alien status and eligibility.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Alien status and eligibility. 1626.5 Section 1626... RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.5 Alien status and eligibility. Subject to all other... may provide legal assistance to an alien who is present in the United States and who is within one...

  17. 26 CFR 1.871-3 - Residence of alien seamen.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 9 2011-04-01 2011-04-01 false Residence of alien seamen. 1.871-3 Section 1.871... (CONTINUED) INCOME TAXES (CONTINUED) Nonresident Aliens and Foreign Corporations § 1.871-3 Residence of alien seamen. In order to determine whether an alien seaman is a resident of the United States for purposes...

  18. 22 CFR 40.91 - Certain aliens previously removed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a...

  19. 47 CFR 90.115 - Foreign government and alien eligibility.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Foreign government and alien eligibility. 90... government and alien eligibility. (a) No station authorization in the radio services governed by this part....9(c) of this chapter) if such entity is: (1) An alien or the representative of any alien; (2)...

  20. 8 CFR 1240.38 - Fingerprinting of excluded aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Fingerprinting of excluded aliens. 1240.38 Section 1240.38 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Exclusion...

  1. 8 CFR 1240.38 - Fingerprinting of excluded aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Fingerprinting of excluded aliens. 1240.38 Section 1240.38 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Exclusion...

  2. 45 CFR 1626.7 - Verification of eligible alien status.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the...

  3. 22 CFR 40.92 - Aliens unlawfully present.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Aliens unlawfully present. 40.92 Section 40.92... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.92 Aliens unlawfully present. (a) 3-year bar. An alien described in INA 212(a)(9)(B)(i)(I) shall be ineligible for...

  4. 8 CFR 274a.3 - Continuing employment of unauthorized aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Continuing employment of unauthorized aliens. 274a.3 Section 274a.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employer Requirements § 274a.3 Continuing employment...

  5. 47 CFR 90.115 - Foreign government and alien eligibility.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Foreign government and alien eligibility. 90... government and alien eligibility. (a) No station authorization in the radio services governed by this part....9(c) of this chapter) if such entity is: (1) An alien or the representative of any alien; (2)...

  6. 31 CFR 515.335 - Permanent resident alien.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States....

  7. 45 CFR 1626.5 - Alien status and eligibility.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false Alien status and eligibility. 1626.5 Section 1626... RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.5 Alien status and eligibility. Subject to all other... may provide legal assistance to an alien who is present in the United States and who is within one...

  8. 45 CFR 233.52 - Overpayment to aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 2 2012-10-01 2012-10-01 false Overpayment to aliens. 233.52 Section 233.52... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall...

  9. 45 CFR 1626.7 - Verification of eligible alien status.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the...

  10. 31 CFR 515.335 - Permanent resident alien.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States....

  11. 45 CFR 1626.7 - Verification of eligible alien status.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the...

  12. 28 CFR 0.47 - Alien property matters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Alien property matters. 0.47 Section 0.47....47 Alien property matters. The Office of Alien Property shall be a part of the Civil Division: (a... Alien Property: (1) Exercising or performing all the authority, rights, privileges, powers, duties,...

  13. 22 CFR 40.92 - Aliens unlawfully present.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Aliens unlawfully present. 40.92 Section 40.92... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.92 Aliens unlawfully present. (a) 3-year bar. An alien described in INA 212(a)(9)(B)(i)(I) shall be ineligible for...

  14. 45 CFR 233.52 - Overpayment to aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 2 2011-10-01 2011-10-01 false Overpayment to aliens. 233.52 Section 233.52... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall...

  15. 22 CFR 40.91 - Certain aliens previously removed.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a...

  16. 8 CFR 274a.3 - Continuing employment of unauthorized aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Continuing employment of unauthorized aliens. 274a.3 Section 274a.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employer Requirements § 274a.3 Continuing employment...

  17. 47 CFR 90.115 - Foreign government and alien eligibility.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Foreign government and alien eligibility. 90... government and alien eligibility. (a) No station authorization in the radio services governed by this part....9(c) of this chapter) if such entity is: (1) An alien or the representative of any alien; (2)...

  18. 7 CFR 273.4 - Citizenship and alien status.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... residing in the same household as the alien at the time of the abuse, an alien whose child has been... residing in the same household as the alien at the time of the abuse, an alien whose child has been... Laotian who is deceased, or (iii) An unmarried dependent child of such Hmong or Highland Laotian who...

  19. 7 CFR 273.4 - Citizenship and alien status.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... residing in the same household as the alien at the time of the abuse, an alien whose child has been... residing in the same household as the alien at the time of the abuse, an alien whose child has been... Laotian who is deceased, or (iii) An unmarried dependent child of such Hmong or Highland Laotian who...

  20. 7 CFR 273.4 - Citizenship and alien status.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... residing in the same household as the alien at the time of the abuse, an alien whose child has been... residing in the same household as the alien at the time of the abuse, an alien whose child has been... Laotian who is deceased, or (iii) An unmarried dependent child of such Hmong or Highland Laotian who...

  1. 7 CFR 273.4 - Citizenship and alien status.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... residing in the same household as the alien at the time of the abuse, an alien whose child has been... residing in the same household as the alien at the time of the abuse, an alien whose child has been... Laotian who is deceased, or (iii) An unmarried dependent child of such Hmong or Highland Laotian who...

  2. 26 CFR 1.871-3 - Residence of alien seamen.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 9 2014-04-01 2014-04-01 false Residence of alien seamen. 1.871-3 Section 1.871... (CONTINUED) INCOME TAXES (CONTINUED) Nonresident Aliens and Foreign Corporations § 1.871-3 Residence of alien seamen. In order to determine whether an alien seaman is a resident of the United States for purposes...

  3. 45 CFR 233.52 - Overpayment to aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 2 2014-10-01 2012-10-01 true Overpayment to aliens. 233.52 Section 233.52 Public... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall...

  4. 31 CFR 515.335 - Permanent resident alien.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States....

  5. 8 CFR 1240.38 - Fingerprinting of excluded aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Fingerprinting of excluded aliens. 1240.38 Section 1240.38 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Exclusion...

  6. 22 CFR 40.92 - Aliens unlawfully present.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Aliens unlawfully present. 40.92 Section 40.92... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.92 Aliens unlawfully present. (a) 3-year bar. An alien described in INA 212(a)(9)(B)(i)(I) shall be ineligible for...

  7. 47 CFR 90.115 - Foreign government and alien eligibility.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Foreign government and alien eligibility. 90... government and alien eligibility. (a) No station authorization in the radio services governed by this part....9(c) of this chapter) if such entity is: (1) An alien or the representative of any alien; (2)...

  8. 8 CFR 274a.3 - Continuing employment of unauthorized aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Continuing employment of unauthorized aliens. 274a.3 Section 274a.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employer Requirements § 274a.3 Continuing employment...

  9. 45 CFR 1626.7 - Verification of eligible alien status.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the...

  10. 26 CFR 1.6654-6 - Nonresident alien individuals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 13 2014-04-01 2014-04-01 false Nonresident alien individuals. 1.6654-6 Section... Penalties § 1.6654-6 Nonresident alien individuals. (a) In general. A nonresident alien individual is... the gross income of a nonresident alien individual is such as to require making a payment of...

  11. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...(c) of 8 CFR chapter I. (b) Service custody and cost of maintenance. An alien confined because of... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT...

  12. 22 CFR 40.91 - Certain aliens previously removed.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a...

  13. Differential rates of phenotypic introgression are associated with male behavioral responses to multiple signals.

    PubMed

    Greig, Emma I; Baldassarre, Daniel T; Webster, Michael S

    2015-10-01

    Sexual selection on multiple signals may lead to differential rates of signal introgression across hybrid zones if some signals contribute to reproductive isolation but others facilitate gene flow. Competition among males is one powerful form of sexual selection, but male behavioral responses to multiple traits have not been considered in a system where traits have introgressed differentially. Using playbacks, mounts, and a reciprocal experimental design, we tested the hypothesis that male responses to song and plumage in two subspecies of red-backed fairy-wren (Malurus melanocephalus) explain patterns of differential signal introgression (song has not introgressed, whereas plumage color has introgressed asymmetrically). We found that males of both subspecies discriminated symmetrically between subspecies' songs at a long range, but at a close range, we found that aggression was equal for both subspecies' plumage and songs. Taken together, our results suggest that male behavioral responses hinder the introgression of song, but allow for the observed asymmetrical introgression of plumage. Our results highlight how behavioral responses are a key component of signal evolution when recently divergent taxa come together, and how differential responses to multiple signals may lead to differential signal introgression and novel trait combinations. PMID:26292844

  14. Genome structure of introgressive lines Triticum aestivum/Aegilops sharonensis.

    PubMed

    Antonyuk, M Z; Bodylyova, M V; Ternovskaya, T K

    2009-01-01

    The lines Triticum aestivum/Aegilops sharonensis were explored in regard to the presence of introgressions in the line genomes, their amount and belonging to definite homoeologic group. The results of studying of chromosome associations in M1 of pollen mother celles in the hybrids between the lines with each other and with recurrent common wheat genotype Avrora were compared with the data of the line assessment for the chromosomal biochemical and morphological markers. 26 lines were distinguished between six groups with specific genome rearrangement regard to recurrent genotype. PMID:20458978

  15. Origin of Gila seminuda (Teleostei: Cyprinidae) through introgressive hybridization: implications for evolution and conservation.

    PubMed Central

    DeMarais, B D; Dowling, T E; Douglas, M E; Minckley, W L; Marsh, P C

    1992-01-01

    Morphological and genetic characters from cyprinid fishes of the genus Gila were examined to assess a hypothesized hybrid origin of Gila seminuda from the Virgin River, Arizona-Nevada-Utah. The presumed parents, Gila robusta robusta and Gila elegans, are clearly differentiated from one another based on morphology, allozymes, and mtDNA haplotypes. G. seminuda is morphologically intermediate and polymorphic at allozyme loci diagnostic for the parental species. Restriction endonuclease analysis of mtDNA showed G. seminuda nearly identical to G. elegans. These results support an origin of the bisexual taxon G. seminuda through introgressive hybridization. The Gila population in the Moapa River, Nevada, also appears to be of hybrid origin and is considered a distinctive population of G. seminuda. Inter-specific hybridization is potentially an important mode of evolution among western North American fishes, and valid species of hybrid origin may exist in other groups as well. Consideration of this mode of evolution argues for the need to conserve entire species complexes. PMID:1557380

  16. Hosts and parasites as aliens.

    PubMed

    Taraschewski, H

    2006-06-01

    Over the past decades, various free-living animals (hosts) and their parasites have invaded recipient areas in which they had not previously occurred, thus gaining the status of aliens or exotics. In general this happened to a low extent for hundreds of years. With variable frequency, invasions have been followed by the dispersal and establishment of non-indigenous species, whether host or parasite. In the literature thus far, colonizations by both hosts and parasites have not been treated and reviewed together, although both are usually interwoven in various ways. As to those factors permitting invasive success and colonization strength, various hypotheses have been put forward depending on the scientific background of respective authors and on the conspicuousness of certain invasions. Researchers who have tried to analyse characteristic developmental patterns, the speed of dispersal or the degree of genetic divergence in populations of alien species have come to different conclusions. Among parasitologists, the applied aspects of parasite invasions, such as the negative effects on economically important hosts, have long been at the centre of interest. In this contribution, invasions by hosts as well as parasites are considered comparatively, revealing many similarities and a few differences. Two helminths, the liver fluke, Fasciola hepatica, of cattle and sheep and the swimbladder nematode, Anguillicola crassus, of eels are shown to be useful as model parasites for the study of animal invasions and environmental global change. Introductions of F. hepatica have been associated with imports of cattle or other grazing animals. In various target areas, susceptible lymnaeid snails serving as intermediate hosts were either naturally present and/or were introduced from the donor continent of the parasite (Europe) and/or from other regions which were not within the original range of the parasite, partly reflecting progressive stages of a global biota change. In several

  17. Extensive Microsatellite Variation in Rice Induced by Introgression from Wild Rice (Zizania latifolia Griseb.)

    PubMed Central

    Dong, Zhenying; Wang, Hongyan; Dong, Yuzhu; Wang, Yongming; Liu, Wei; Miao, Gaojian; Lin, Xiuyun; Wang, Daqing; Liu, Bao

    2013-01-01

    Background It is widely accepted that interspecific hybridization may induce genomic instability in the resultant hybrids. However, few studies have been performed on the genomic analysis of homoploid hybrids and introgression lines. We have reported previously that by introgressive hybridization, a set of introgression lines between rice (Oryza sativa L.) and wild rice (Zizania latifolia Griseb.) was successfully generated, and which have led to the release of several cultivars. Methodology Using 96 microsatellite markers located in the nuclear and organelle genomes of rice, we investigated microsatellite stability in three typical introgression lines. Expression of a set of mismatch repair (MMR) genes and microsatellite-containing genes was also analyzed. Results/Conclusions Compared with the recipient rice cultivar (Matsumae), 55 of the 96 microsatellite loci revealed variation in one or more of the introgression lines, and 58.2% of the altered alleles were shared by at least two lines, indicating that most of the alterations had occurred in the early stages of introgression before their further differentiation. 73.9% of the non-shared variations were detected only in one introgression line, i.e. RZ2. Sequence alignment showed that the variations included substitutions and indels that occurred both within the repeat tracts and in the flanking regions. Interestingly, expression of a set of MMR genes altered dramatically in the introgression lines relative to their rice parent, suggesting participation of the MMR system in the generation of microsatellite variants. Some of the altered microsatellite loci are concordant with changed expression of the genes harboring them, suggesting their possible cis-regulatory roles in controlling gene expression. Because these genes bear meaningful homology to known-functional proteins, we conclude that the introgression-induced extensive variation of microsatellites may have contributed to the novel phenotypes in the

  18. DNA.

    ERIC Educational Resources Information Center

    Felsenfeld, Gary

    1985-01-01

    Structural form, bonding scheme, and chromatin structure of and gene-modification experiments with deoxyribonucleic acid (DNA) are described. Indicates that DNA's double helix is variable and also flexible as it interacts with regulatory and other molecules to transfer hereditary messages. (DH)

  19. Interspecific Hybridization in Pilot Whales and Asymmetric Genetic Introgression in Northern Globicephala melas under the Scenario of Global Warming

    PubMed Central

    Miralles, Laura; Oremus, Marc; Silva, Mónica A.; Planes, Serge; Garcia-Vazquez, Eva

    2016-01-01

    Pilot whales are two cetacean species (Globicephala melas and G. macrorhynchus) whose distributions are correlated with water temperature and partially overlap in some areas like the North Atlantic Ocean. In the context of global warming, distribution range shifts are expected to occur in species affected by temperature. Consequently, a northward displacement of the tropical pilot whale G. macrorynchus is expected, eventually leading to increased secondary contact areas and opportunities for interspecific hybridization. Here, we describe genetic evidences of recurrent hybridization between pilot whales in northeast Atlantic Ocean. Based on mitochondrial DNA sequences and microsatellite loci, asymmetric introgression of G. macrorhynchus genes into G. melas was observed. For the latter species, a significant correlation was found between historical population growth rate estimates and paleotemperature oscillations. Introgressive hybridization, current temperature increases and lower genetic variation in G. melas suggest that this species could be at risk in its northern range. Under increasing environmental and human-mediated stressors in the North Atlantic Ocean, it seems recommendable to develop a conservation program for G. melas. PMID:27508496

  20. Interspecific Hybridization in Pilot Whales and Asymmetric Genetic Introgression in Northern Globicephala melas under the Scenario of Global Warming.

    PubMed

    Miralles, Laura; Oremus, Marc; Silva, Mónica A; Planes, Serge; Garcia-Vazquez, Eva

    2016-01-01

    Pilot whales are two cetacean species (Globicephala melas and G. macrorhynchus) whose distributions are correlated with water temperature and partially overlap in some areas like the North Atlantic Ocean. In the context of global warming, distribution range shifts are expected to occur in species affected by temperature. Consequently, a northward displacement of the tropical pilot whale G. macrorynchus is expected, eventually leading to increased secondary contact areas and opportunities for interspecific hybridization. Here, we describe genetic evidences of recurrent hybridization between pilot whales in northeast Atlantic Ocean. Based on mitochondrial DNA sequences and microsatellite loci, asymmetric introgression of G. macrorhynchus genes into G. melas was observed. For the latter species, a significant correlation was found between historical population growth rate estimates and paleotemperature oscillations. Introgressive hybridization, current temperature increases and lower genetic variation in G. melas suggest that this species could be at risk in its northern range. Under increasing environmental and human-mediated stressors in the North Atlantic Ocean, it seems recommendable to develop a conservation program for G. melas. PMID:27508496

  1. Development of β-Carotene Rich Maize Hybrids through Marker-Assisted Introgression of β-carotene hydroxylase Allele

    PubMed Central

    Muthusamy, Vignesh; Hossain, Firoz; Thirunavukkarasu, Nepolean; Choudhary, Mukesh; Saha, Supradip; Bhat, Jayant S.; Prasanna, Boddupalli M.; Gupta, Hari S.

    2014-01-01

    Development of vitamin A-rich cereals can help in alleviating the widespread problem of vitamin A deficiency. We report here significant enhancement of kernel β-carotene in elite maize genotypes through accelerated marker-assisted backcross breeding. A favourable allele (543 bp) of the β-carotene hydroxylase (crtRB1) gene was introgressed in the seven elite inbred parents, which were low (1.4 µg/g) in kernel β-carotene, by using a crtRB1-specific DNA marker for foreground selection. About 90% of the recurrent parent genome was recovered in the selected progenies within two backcross generations. Concentration of β-carotene among the crtRB1-introgressed inbreds varied from 8.6 to 17.5 µg/g - a maximum increase up to 12.6-fold over recurrent parent. The reconstituted hybrids developed from improved parental inbreds also showed enhanced kernel β-carotene as high as 21.7 µg/g, compared to 2.6 µg/g in the original hybrid. The reconstituted hybrids evaluated at two locations possessed similar grain yield to that of original hybrids. These β-carotene enriched high yielding hybrids can be effectively utilized in the maize biofortification programs across the globe. PMID:25486271

  2. From speciation to introgressive hybridization: the phylogeographic structure of an island subspecies of termite, Reticulitermes lucifugus corsicus

    PubMed Central

    2008-01-01

    Background Although much research has been carried out into European Reticulitermes taxonomy in recent years, there is still much discussion about phylogenetic relationships. This study investigated the evolution from intra- to interspecific phylogeny in the island subspecies Reticulitermes lucifugus corsicus and threw new light on this phenomenon. An integrative approach based on microsatellites and mitochondrial and nuclear DNA sequences was used to analyze samples taken from a wide area around the Tyrrhenian sea and showed how the subspecies evolved from its origins to its most recent form on continental coasts. Results According to mitochondrial phylogeny and molecular clock calculations, island and continental taxa diverged significantly by vicariance in the Pleistocene glacial period. However, more recently, numerous migrations, certainly human-mediated, affected the structure of the populations. This study provided evidence of direct hybridization and multiple introgressions which occurred in several hybrid areas. Analysis using STRUCTURE based on microsatellite data identified a population in Provence (France) which differed considerably (Fst = 0.477) from populations on the island of Corsica and in Tuscany in the Italian peninsula. This new population, principally distributed in urban areas, is highly heterogeneous especially within the ITS2 regions where homogenization by concerted evolution does not appear to have been completed. Conclusion This study provides an unusual picture of genetic interaction between termite populations in the Tyrrhenian area and suggests that more attention should be paid to the role of introgression and human impact on the recent evolution of European termites. PMID:18248672

  3. Introgressive Hybridization between Anciently Diverged Lineages of Silene (Caryophyllaceae)

    PubMed Central

    Petri, Anna; Pfeil, Bernard E.; Oxelman, Bengt

    2013-01-01

    Hybridization has played a major role during the evolution of angiosperms, mediating both gene flow between already distinct species and the formation of new species. Newly formed hybrids between distantly related taxa are often sterile. For this reason, interspecific crosses resulting in fertile hybrids have rarely been described to take place after more than a few million years after divergence. We describe here the traces of a reproductively successful hybrid between two ancestral species of Silene, diverged for about six million years prior to hybridization. No extant hybrids between the two parental lineages are currently known, but introgression of the RNA polymerase gene NRPA2 provides clear evidence of a temporary and fertile hybrid. Parsimony reconciliation between gene trees and the species tree, as well as consideration of clade ages, help exclude gene paralogy and lineage sorting as alternative hypotheses. This may represent one of the most extreme cases of divergence between species prior to introgressive hybridization discovered yet, notably at a homoploid level. Although species boundaries are generally believed to be stable after millions of years of divergence, we believe that this finding may indicate that gene flow between distantly related species is merely largely undetected at present. PMID:23861793

  4. Efficient nonmeiotic allele introgression in livestock using custom endonucleases

    PubMed Central

    Tan, Wenfang; Carlson, Daniel F.; Lancto, Cheryl A.; Garbe, John R.; Webster, Dennis A.; Hackett, Perry B.; Fahrenkrug, Scott C.

    2013-01-01

    We have expanded the livestock gene editing toolbox to include transcription activator-like (TAL) effector nuclease (TALEN)- and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-stimulated homology-directed repair (HDR) using plasmid, rAAV, and oligonucleotide templates. Toward the genetic dehorning of dairy cattle, we introgressed a bovine POLLED allele into horned bull fibroblasts. Single nucleotide alterations or small indels were introduced into 14 additional genes in pig, goat, and cattle fibroblasts using TALEN mRNA and oligonucleotide transfection with efficiencies of 10–50% in populations. Several of the chosen edits mimic naturally occurring performance-enhancing or disease- resistance alleles, including alteration of single base pairs. Up to 70% of the fibroblast colonies propagated without selection harbored the intended edits, of which more than one-half were homozygous. Edited fibroblasts were used to generate pigs with knockout alleles in the DAZL and APC genes to model infertility and colon cancer. Our methods enable unprecedented meiosis-free intraspecific and interspecific introgression of select alleles in livestock for agricultural and biomedical applications. PMID:24014591

  5. Genetic Introgression and the Survival of Florida Panther Kittens

    PubMed Central

    Hostetler, Jeffrey A.; Onorato, David P.; Nichols, James D.; Johnson, Warren E.; Roelke, Melody E.; O’Brien, Stephen J.; Jansen, Deborah; Oli, Madan K.

    2010-01-01

    Estimates of survival for the young of a species are critical for population models. These models can often be improved by determining the effects of management actions and population abundance on this demographic parameter. We used multiple sources of data collected during 1982-2008 and a live recapture-dead recovery modeling framework to estimate and model survival of Florida panther (Puma concolor coryi) kittens (age 0 – 1 year). Overall, annual survival of Florida panther kittens was 0.323 ± 0.071 (SE), which was lower than estimates used in previous population models. In 1995, female pumas from Texas (P. c. stanleyana) were released into occupied panther range as part of an intentional introgression program to restore genetic variability. We found that kitten survival generally increased with degree of admixture: F1 admixed and backcrossed to Texas kittens survived better than canonical Florida panther and backcrossed to canonical kittens. Average heterozygosity positively influenced kitten and older panther survival, whereas index of panther abundance negatively influenced kitten survival. Our results provide strong evidence for the positive population-level impact of genetic introgression on Florida panthers. Our approach to integrate data from multiple sources was effective at improving robustness as well as precision of estimates of Florida panther kitten survival, and can be useful in estimating vital rates for other elusive species with sparse data. PMID:21113436

  6. Genetic Introgression and the Survival of Florida Panther Kittens.

    PubMed

    Hostetler, Jeffrey A; Onorato, David P; Nichols, James D; Johnson, Warren E; Roelke, Melody E; O'Brien, Stephen J; Jansen, Deborah; Oli, Madan K

    2010-11-01

    Estimates of survival for the young of a species are critical for population models. These models can often be improved by determining the effects of management actions and population abundance on this demographic parameter. We used multiple sources of data collected during 1982-2008 and a live recapture-dead recovery modeling framework to estimate and model survival of Florida panther (Puma concolor coryi) kittens (age 0 - 1 year). Overall, annual survival of Florida panther kittens was 0.323 ± 0.071 (SE), which was lower than estimates used in previous population models. In 1995, female pumas from Texas (P. c. stanleyana) were released into occupied panther range as part of an intentional introgression program to restore genetic variability. We found that kitten survival generally increased with degree of admixture: F(1) admixed and backcrossed to Texas kittens survived better than canonical Florida panther and backcrossed to canonical kittens. Average heterozygosity positively influenced kitten and older panther survival, whereas index of panther abundance negatively influenced kitten survival. Our results provide strong evidence for the positive population-level impact of genetic introgression on Florida panthers. Our approach to integrate data from multiple sources was effective at improving robustness as well as precision of estimates of Florida panther kitten survival, and can be useful in estimating vital rates for other elusive species with sparse data. PMID:21113436

  7. Genetic introgression and the survival of Florida panther kittens

    USGS Publications Warehouse

    Hostetler, Jeffrey A.; Onorato, David P.; Nichols, James D.; Johnson, Warren E.; Roelke, Melody E.; O'Brien, Stephen J.; Jansen, Deborah; Oli, Madan K.

    2010-01-01

    Estimates of survival for the young of a species are critical for population models. These models can often be improved by determining the effects of management actions and population abundance on this demographic parameter. We used multiple sources of data collected during 1982-2008 and a live-recapture dead-recovery modeling framework to estimate and model survival of Florida panther (Puma concolor coryi) kittens (age 0-1 year). Overall, annual survival of Florida panther kittens was 0.323 + or - 0.071 (SE), which was lower than estimates used in previous population models. In 1995, female pumas from Texas (P. c. stanleyana) were released into occupied panther range as part of an intentional introgression program to restore genetic variability. We found that kitten survival generally increased with degree of admixture: F1 admixed and backcrossed to Texas kittens survived better than canonical Florida panther and backcrossed to canonical kittens. Average heterozygosity positively influenced kitten and older panther survival, whereas index of panther abundance negatively influenced kitten survival. Our results provide strong evidence for the positive population-level impact of genetic introgression on Florida panthers. Our approach to integrate data from multiple sources was effective at improving robustness as well as precision of estimates of Florida panther kitten survival, and can be useful in estimating vital rates for other elusive species with sparse data.

  8. Undocumented Aliens: A Study of Mexican Families.

    ERIC Educational Resources Information Center

    Salcido, Ramon M.

    1979-01-01

    The personal histories described here confirm that the primary impetus of undocumented aliens to emigrate is the desire for jobs and better socioeconomic opportunities. Amnesty, aid to families with dependent children, and increased social services are recommended. (Author/BEF)

  9. Detection and Polarization of Introgression in a Five-Taxon Phylogeny.

    PubMed

    Pease, James B; Hahn, Matthew W

    2015-07-01

    When multiple speciation events occur rapidly in succession, discordant genealogies due to incomplete lineage sorting (ILS) can complicate the detection of introgression. A variety of methods, including the [Formula: see text]-statistic (a.k.a. the "ABBA-BABA test"), have been proposed to infer introgression in the presence of ILS for a four-taxon clade. However, no integrated method exists to detect introgression using allelic patterns for more complex phylogenies. Here we explore the issues associated with previous systems of applying [Formula: see text]-statistics to a larger tree topology, and propose new [Formula: see text] tests as an integrated framework to infer both the taxa involved in and the direction of introgression for a symmetric five-taxon phylogeny. Using theory and simulations, we show that the [Formula: see text] statistics correctly identify the introgression donor and recipient lineages, even at low rates of introgression. [Formula: see text] is also shown to have extremely low false-positive rates. The [Formula: see text] tests are computationally inexpensive to calculate and can easily be applied to phylogenomic data sets, both genome-wide and in windows of the genome. In addition, we explore both the principles and problems of introgression detection in even more complex phylogenies. PMID:25888025

  10. Chromosome elimination, addition and introgression in intertribal partial hybrids between Brassica rapa and Isatis indigotica

    PubMed Central

    Tu, Yuqin; Sun, Jian; Ge, Xianhong; Li, Zaiyun

    2009-01-01

    Background and Aims Partial hybrids with female-parent-type phenotypes and chromosome numbers but altered genomic compositions have been reported in wide crosses of several plants. In order to introgress desirable genes from a wild relative, Isatis indigotica (a dye and medicinal plant; 2n = 14), into Brassica crops, intertribal sexual hybridizations were carried out with B. rapa (2n = 20), and the resulting hybrids and their progenies were characterized. Methods Using genomic in situ hybridization (GISH) and amplified fragment length polymorphism (AFLP), chromosomal/genomic components of the hybrids and their progenies were analysed. Key Results Many hybrid plants were obtained from the mature seeds harvested from the B. rapa × I. indigotica cross, and these exhibited different morphological traits. However, the majority of them did not survive and only three plants grew to maturity. These three hybrids showed poor growth and much smaller stature than the two parents, but had some morphological traits and chemical composition of I. indigotica. One plant had 2n = 10, the haploid chromosome number of B. rapa, and was absolutely sterile. The other two plants had 20 and 22 somatic chromosomes and were male sterile but produced seeds following pollinations with B. rapa. All back-cross progenies over several generations maintained a B. rapa-type phenotype and also displayed some variations in morphological characters and fatty acid compositions. They were all 2n = 20 and showed good seed-set. The hybrid with 2n = 22 produced some progeny plants with 2n = 21 and 2n = 22. GISH detected two chromosomes of I. indigotica in the hybrid with 2n = 22 but none in the one with 2n = 20. AFLP bands specific for I. indigotica, novel for two parents or absent in B. rapa, were detected in the two hybrids and their progenies. These progeny plants were novel B. rapa types with an altered genomic constitution or alien additions. Conclusions Complete or partial chromosome elimination and

  11. An HMM-Based Comparative Genomic Framework for Detecting Introgression in Eukaryotes

    PubMed Central

    Liu, Kevin J.; Dai, Jingxuan; Truong, Kathy; Song, Ying; Kohn, Michael H.; Nakhleh, Luay

    2014-01-01

    One outcome of interspecific hybridization and subsequent effects of evolutionary forces is introgression, which is the integration of genetic material from one species into the genome of an individual in another species. The evolution of several groups of eukaryotic species has involved hybridization, and cases of adaptation through introgression have been already established. In this work, we report on PhyloNet-HMM—a new comparative genomic framework for detecting introgression in genomes. PhyloNet-HMM combines phylogenetic networks with hidden Markov models (HMMs) to simultaneously capture the (potentially reticulate) evolutionary history of the genomes and dependencies within genomes. A novel aspect of our work is that it also accounts for incomplete lineage sorting and dependence across loci. Application of our model to variation data from chromosome 7 in the mouse (Mus musculus domesticus) genome detected a recently reported adaptive introgression event involving the rodent poison resistance gene Vkorc1, in addition to other newly detected introgressed genomic regions. Based on our analysis, it is estimated that about 9% of all sites within chromosome 7 are of introgressive origin (these cover about 13 Mbp of chromosome 7, and over 300 genes). Further, our model detected no introgression in a negative control data set. We also found that our model accurately detected introgression and other evolutionary processes from synthetic data sets simulated under the coalescent model with recombination, isolation, and migration. Our work provides a powerful framework for systematic analysis of introgression while simultaneously accounting for dependence across sites, point mutations, recombination, and ancestral polymorphism. PMID:24922281

  12. Genetic dissection of maize phenology using an intraspecific introgression library

    PubMed Central

    2011-01-01

    Background Collections of nearly isogenic lines where each line carries a delimited portion of a donor source genome into a common recipient genetic background are known as introgression libraries and have already shown to be instrumental for the dissection of quantitative traits. By means of marker-assisted backcrossing, we have produced an introgression library using the extremely early-flowering maize (Zea mays L.) variety Gaspé Flint and the elite line B73 as donor and recipient genotypes, respectively, and utilized this collection to investigate the genetic basis of flowering time and related traits of adaptive and agronomic importance in maize. Results The collection includes 75 lines with an average Gaspé Flint introgression length of 43.1 cM. The collection was evaluated for flowering time, internode length, number of ears, number of nodes (phytomeres), number of nodes above the ear, number and proportion of nodes below the ear and plant height. Five QTLs for flowering time were mapped, all corresponding to major QTLs for number of nodes. Three additional QTLs for number of nodes were mapped. Besides flowering time, the QTLs for number of nodes drove phenotypic variation for plant height and number of nodes below and above the top ear, but not for internode length. A number of apparently Mendelian-inherited phenotypes were also observed. Conclusions While the inheritance of flowering time was dominated by the well-known QTL Vgt1, a number of other important flowering time QTLs were identified and, thanks to the type of plant material here utilized, immediately isogenized and made available for fine mapping. At each flowering time QTL, early flowering correlated with fewer vegetative phytomeres, indicating the latter as a key developmental strategy to adapt the maize crop from the original tropical environment to the northern border of the temperate zone (southern Canada), where Gaspé Flint was originally cultivated. Because of the trait differences

  13. Phylogenetic evidence of historic mitochondrial introgression and cryptic diversity in the genus Pseudemoia (Squamata: Scincidae).

    PubMed

    Haines, Margaret L; Moussalli, Adnan; Stuart-Fox, Devi; Clemann, Nick; Melville, Jane

    2014-12-01

    The Australian scincid genus Pseudemoia comprises six morphologically similar species restricted to temperate south-eastern Australia. Due to the high degree of morphological conservatism, phylogenetic relationships and taxonomic status within the Pseudemoia entrecasteauxii complex (comprising the nominal species P. entrecasteauxii, P. cryodroma, and P. pagenstecheri) remains unresolved. To further investigate the phylogenetic relationships and taxonomic status of Pseudemoia spp., and to test the hypothesis that P. cryodroma evolved from hybridization between P. entrecasteauxii and P. pagenstecheri, we sequenced one mitochondrial locus (ND4) and five nuclear loci (β-globin, LGMN, PRLR, Rhodopsin, RPS8). While we find strong support for the monophyly of the P. entrecasteauxii complex, there exists marked incongruence between the mitochondrial and nuclear markers, particularly in regards to the high altitude specialist, P. cryodroma. The most parsimonious explanation of this discordance is historic mitochondrial introgression, although a hybrid origin for P. cryodroma cannot be completely rejected. Within P. pagenstecheri sensu lato, we identified a strongly supported, highly divergent yet morphologically cryptic lineage restricted to northern New South Wales. Although more weakly supported by the nuDNA, we also identified a second geographically distinct lineage of P. pagenstecheri s.l., which may warrant separate conservation management. Our study reveals a more complex evolutionary history of the genus Pseudemoia than previously appreciated and contributes to our understanding of the biogeography and evolution of Australian mesic zone fauna. PMID:25242002

  14. Detection of genetic diversity and selective gene introgression in coffee using RAPD markers.

    PubMed

    Orozco-Castillo, C; Chalmers, K J; Waugh, R; Powell, W

    1994-03-01

    RAPD (randomly amplified polymorphic DNA) markers generated by arbitary decamers have been successfully employed to detect genetic polymorphisms between coffee species and between Coffea arabica genotypes. The RAPD profiles were used to construct dendrograms and these were consistent with the known history and evolution of Coffea arabica. Material originating from Ethiopia and the arabica sub-groups - C. arabica var. typica and C. arabica var. bourbon - were clearly distinguished. RAPD analysis therefore reflects morphological differences between the sub-groups and the geographical origin of the coffee material. Species-specific amplification products were also identified, but, more importantly, amplification products specific to C. canephora were identified in two C. arabica genotypes, Rume Sudan and Catimor 5175. This diagnostic product is therefore indicative of interspecific gene flow in coffee and has biological implications for selective introgressive hybridisation in coffee. Our study demonstrates the power of the polymerase chain reaction technology for the generation of genetic markers for long-lived perennial tree and bush crops. PMID:24190527

  15. Introgression potential between safflower (Carthamus tinctorius) and wild relatives of the genus Carthamus

    PubMed Central

    2011-01-01

    Background Safflower, Carthamus tinctorius, is a thistle that is grown commercially for the production of oil and birdseed and recently, as a host for the production of transgenic pharmaceutical proteins. C. tinctorius can cross with a number of its wild relatives, creating the possibility of gene flow from safflower to weedy species. In this study we looked at the introgression potential between different members of the genus Carthamus, measured the fitness of the parents versus the F1 hybrids, followed the segregation of a specific transgene in the progeny and tried to identify traits important for adaptation to different environments. Results Safflower hybridized and produced viable offspring with members of the section Carthamus and species with chromosome numbers of n = 10 and n = 22, but not with n = 32. The T-DNA construct of a transgenic C. tinctorius line was passed on to the F1 progeny in a Mendelian fashion, except in one specific cross, where it was deleted at a frequency of approximately 21%. Analyzing fitness and key morphological traits like colored seeds, shattering seed heads and the presence of a pappus, we found no evidence of hybrid vigour or increased weediness in the F1 hybrids of commercial safflower and its wild relatives. Conclusion Our results suggest that hybridization between commercial safflower and its wild relatives, while feasible in most cases we studied, does not generate progeny with higher propensity for weediness. PMID:21401959

  16. Molecular analysis, cytogenetics and fertility of introgression lines from transgenic wheat to Aegilops cylindrica host.

    PubMed

    Schoenenberger, Nicola; Guadagnuolo, Roberto; Savova-Bianchi, Dessislava; Küpfer, Philippe; Felber, François

    2006-12-01

    Natural hybridization and backcrossing between Aegilops cylindrica and Triticum aestivum can lead to introgression of wheat DNA into the wild species. Hybrids between Ae. cylindrica and wheat lines bearing herbicide resistance (bar), reporter (gus), fungal disease resistance (kp4), and increased insect tolerance (gna) transgenes were produced by pollination of emasculated Ae. cylindrica plants. F1 hybrids were backcrossed to Ae. cylindrica under open-pollination conditions, and first backcrosses were selfed using pollen bags. Female fertility of F1 ranged from 0.03 to 0.6%. Eighteen percent of the sown BC1s germinated and flowered. Chromosome numbers ranged from 30 to 84 and several of the plants bore wheat-specific sequence-characterized amplified regions (SCARs) and the bar gene. Self fertility in two BC1 plants was 0.16 and 5.21%, and the others were completely self-sterile. Among 19 BC1S1 individuals one plant was transgenic, had 43 chromosomes, contained the bar gene, and survived glufosinate treatments. The other BC1S1 plants had between 28 and 31 chromosomes, and several of them carried SCARs specific to wheat A and D genomes. Fertility of these plants was higher under open-pollination conditions than by selfing and did not necessarily correlate with even or euploid chromosome number. Some individuals having supernumerary wheat chromosomes recovered full fertility. PMID:17028347

  17. A genomic view of introgression and hybrid speciation

    PubMed Central

    Baack, Eric J.; Rieseberg, Loren H.

    2007-01-01

    Summary Hybridization in plants and animals is more common and has more complex outcomes than previously realized. Genome-wide analyses of introgression in organisms ranging from oaks to sunflowers to fruit flies show that a substantial fraction of their genomes are permeable to alleles from related species. Hybridization can lead to rapid genomic changes, including chromosomal rearrangements, genome expansion, differential gene expression, and gene silencing, some of which are mediated by transposable elements. These genomic changes may lead to beneficial new phenotypes, and selection for fertility and ecological traits may in turn alter genome structure. Dramatic increases in the availability of genomic tools will produce a new understanding of the genetic nature of species and will resolve a century-old debate over the basis of hybrid vigour, while the natural recombinants found in hybrid zones will permit genetic mapping of species differences and reproductive barriers in non-model organisms. PMID:17933508

  18. Speciation and Introgression between Mimulus nasutus and Mimulus guttatus

    PubMed Central

    Flagel, Lex; Coop, Graham; Sweigart, Andrea L.

    2014-01-01

    Mimulus guttatus and M. nasutus are an evolutionary and ecological model sister species pair differentiated by ecology, mating system, and partial reproductive isolation. Despite extensive research on this system, the history of divergence and differentiation in this sister pair is unclear. We present and analyze a population genomic data set which shows that M. nasutus budded from a central Californian M. guttatus population within the last 200 to 500 thousand years. In this time, the M. nasutus genome has accrued genomic signatures of the transition to predominant selfing, including an elevated proportion of nonsynonymous variants, an accumulation of premature stop codons, and extended levels of linkage disequilibrium. Despite clear biological differentiation, we document genomic signatures of ongoing, bidirectional introgression. We observe a negative relationship between the recombination rate and divergence between M. nasutus and sympatric M. guttatus samples, suggesting that selection acts against M. nasutus ancestry in M. guttatus. PMID:24967630

  19. DNA

    ERIC Educational Resources Information Center

    Stent, Gunther S.

    1970-01-01

    This history for molecular genetics and its explanation of DNA begins with an analysis of the Golden Jubilee essay papers, 1955. The paper ends stating that the higher nervous system is the one major frontier of biological inquiry which still offers some romance of research. (Author/VW)

  20. 8 CFR 274a.12 - Classes of aliens authorized to accept employment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Classes of aliens authorized to accept employment. 274a.12 Section 274a.12 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employment Authorization § 274a.12 Classes of aliens authorized to accept employment. (a) Aliens...

  1. Adaptive introgression between Anopheles sibling species eliminates a major genomic island but not reproductive isolation.

    PubMed

    Clarkson, Chris S; Weetman, David; Essandoh, John; Yawson, Alexander E; Maslen, Gareth; Manske, Magnus; Field, Stuart G; Webster, Mark; Antão, Tiago; MacInnis, Bronwyn; Kwiatkowski, Dominic; Donnelly, Martin J

    2014-01-01

    Adaptive introgression can provide novel genetic variation to fuel rapid evolutionary responses, though it may be counterbalanced by potential for detrimental disruption of the recipient genomic background. We examine the extent and impact of recent introgression of a strongly selected insecticide-resistance mutation (Vgsc-1014F) located within one of two exceptionally large genomic islands of divergence separating the Anopheles gambiae species pair. Here we show that transfer of the Vgsc mutation results in homogenization of the entire genomic island region (~1.5% of the genome) between species. Despite this massive disruption, introgression is clearly adaptive with a dramatic rise in frequency of Vgsc-1014F and no discernable impact on subsequent reproductive isolation between species. Our results show (1) how resilience of genomes to massive introgression can permit rapid adaptive response to anthropogenic selection and (2) that even extreme prominence of genomic islands of divergence can be an unreliable indicator of importance in speciation. PMID:24963649

  2. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    EPA Science Inventory

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  3. 32 CFR 1630.46 - Class 4-T: Treaty alien.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Class 4-T: Treaty alien. 1630.46 Section 1630.46 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.46 Class 4-T: Treaty alien. In Class 4-T shall be placed any registrant who is an alien...

  4. 32 CFR 1602.3 - Aliens and nationals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Aliens and nationals. 1602.3 Section 1602.3 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.3 Aliens and nationals. (a) The term alien means any person who is not a citizen or national of...

  5. 22 CFR 41.58 - Aliens in religious occupations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Aliens in religious occupations. 41.58 Section... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.58 Aliens in religious occupations. (a) Requirements for “R” classification. An alien shall be classifiable under the provisions of...

  6. 20 CFR 404.1036 - Certain nonresident aliens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Certain nonresident aliens. 404.1036 Section... Employment § 404.1036 Certain nonresident aliens. (a) Foreign students. (1) Foreign students (nonimmigrant aliens) may be temporarily in the United States under subparagraph (F) of section 101(a)(15) of...

  7. 8 CFR 1241.20 - Aliens ordered excluded.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., see 8 CFR 241.20 through 241.25. ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Aliens ordered excluded. 1241.20 Section 1241.20 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  8. 42 CFR 436.330 - Coverage for certain aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain aliens. 436.330 Section 436... Coverage of the Medically Needy § 436.330 Coverage for certain aliens. If an agency provides Medicaid to... condition, as defined in § 440.255(c) of this chapter to those aliens described in § 436.406(c) of...

  9. 45 CFR 233.51 - Eligibility of sponsored aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 2 2012-10-01 2012-10-01 false Eligibility of sponsored aliens. 233.51 Section... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor...

  10. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....1 of this chapter upon the person or persons specified by 8 CFR 103.8(c). (b) Service custody and... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION...

  11. 32 CFR 1630.46 - Class 4-T: Treaty alien.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Class 4-T: Treaty alien. 1630.46 Section 1630.46 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.46 Class 4-T: Treaty alien. In Class 4-T shall be placed any registrant who is an alien...

  12. 22 CFR 41.58 - Aliens in religious occupations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Aliens in religious occupations. 41.58 Section... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.58 Aliens in religious occupations. (a) Requirements for “R” classification. An alien shall be classifiable under the provisions of...

  13. 45 CFR 233.51 - Eligibility of sponsored aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 2 2011-10-01 2011-10-01 false Eligibility of sponsored aliens. 233.51 Section... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor...

  14. 32 CFR 1630.46 - Class 4-T: Treaty alien.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Class 4-T: Treaty alien. 1630.46 Section 1630.46 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.46 Class 4-T: Treaty alien. In Class 4-T shall be placed any registrant who is an alien...

  15. 32 CFR 1630.46 - Class 4-T: Treaty alien.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Class 4-T: Treaty alien. 1630.46 Section 1630.46 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.46 Class 4-T: Treaty alien. In Class 4-T shall be placed any registrant who is an alien...

  16. 8 CFR 1241.30 - Aliens ordered deported.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ordered deported, see 8 CFR 241.30 through 241.33. ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Aliens ordered deported. 1241.30 Section 1241.30 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  17. 22 CFR 41.55 - Aliens with extraordinary ability.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Aliens with extraordinary ability. 41.55... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.55 Aliens with extraordinary ability. (a) Requirements for O classification. An alien shall be classifiable under the provisions of INA...

  18. 45 CFR 233.51 - Eligibility of sponsored aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 2 2013-10-01 2012-10-01 true Eligibility of sponsored aliens. 233.51 Section 233... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor...

  19. 8 CFR 1241.30 - Aliens ordered deported.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ordered deported, see 8 CFR 241.30 through 241.33. ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Aliens ordered deported. 1241.30 Section 1241.30 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  20. 8 CFR 1241.20 - Aliens ordered excluded.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., see 8 CFR 241.20 through 241.25. ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Aliens ordered excluded. 1241.20 Section 1241.20 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  1. 22 CFR 41.55 - Aliens with extraordinary ability.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens with extraordinary ability. 41.55... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.55 Aliens with extraordinary ability. (a) Requirements for O classification. An alien shall be classifiable under the provisions of INA...

  2. 20 CFR 404.1036 - Certain nonresident aliens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Certain nonresident aliens. 404.1036 Section... Employment § 404.1036 Certain nonresident aliens. (a) Foreign students. (1) Foreign students (nonimmigrant aliens) may be temporarily in the United States under subparagraph (F) of section 101(a)(15) of...

  3. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart....

  4. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart....

  5. 45 CFR 233.51 - Eligibility of sponsored aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Eligibility of sponsored aliens. 233.51 Section... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor...

  6. 42 CFR 436.330 - Coverage for certain aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Coverage for certain aliens. 436.330 Section 436... Coverage of the Medically Needy § 436.330 Coverage for certain aliens. If an agency provides Medicaid to... condition, as defined in § 440.255(c) of this chapter to those aliens described in § 436.406(c) of...

  7. 8 CFR 1241.30 - Aliens ordered deported.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ordered deported, see 8 CFR 241.30 through 241.33. ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Aliens ordered deported. 1241.30 Section 1241.30 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  8. 32 CFR 1602.3 - Aliens and nationals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Aliens and nationals. 1602.3 Section 1602.3 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.3 Aliens and nationals. (a) The term alien means any person who is not a citizen or national of...

  9. 22 CFR 41.55 - Aliens with extraordinary ability.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Aliens with extraordinary ability. 41.55... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.55 Aliens with extraordinary ability. (a) Requirements for O classification. An alien shall be classifiable under the provisions of INA...

  10. 42 CFR 436.330 - Coverage for certain aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Coverage for certain aliens. 436.330 Section 436... Coverage of the Medically Needy § 436.330 Coverage for certain aliens. If an agency provides Medicaid to... condition, as defined in § 440.255(c) of this chapter to those aliens described in § 436.406(c) of...

  11. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in...

  12. 22 CFR 40.9 - Classes of inadmissible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to...

  13. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart....

  14. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in...

  15. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  16. 22 CFR 41.58 - Aliens in religious occupations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Aliens in religious occupations. 41.58 Section... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.58 Aliens in religious occupations. (a) Requirements for “R” classification. An alien shall be classifiable under the provisions of...

  17. 42 CFR 436.330 - Coverage for certain aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Coverage for certain aliens. 436.330 Section 436... Coverage of the Medically Needy § 436.330 Coverage for certain aliens. If an agency provides Medicaid to... condition, as defined in § 440.255(c) of this chapter to those aliens described in § 436.406(c) of...

  18. 20 CFR 404.1036 - Certain nonresident aliens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Certain nonresident aliens. 404.1036 Section... Employment § 404.1036 Certain nonresident aliens. (a) Foreign students. (1) Foreign students (nonimmigrant aliens) may be temporarily in the United States under subparagraph (F) of section 101(a)(15) of...

  19. 22 CFR 40.9 - Classes of inadmissible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to...

  20. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  1. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in...

  2. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart....

  3. 22 CFR 40.9 - Classes of inadmissible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to...

  4. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....1 of this chapter upon the person or persons specified by 8 CFR 103.8(c). (b) Service custody and... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION...

  5. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Coverage for certain aliens. 435.139 Section 435... ISLANDS, AND AMERICAN SAMOA Mandatory Coverage Mandatory Coverage of Certain Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency...

  6. 32 CFR 1602.3 - Aliens and nationals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Aliens and nationals. 1602.3 Section 1602.3 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.3 Aliens and nationals. (a) The term alien means any person who is not a citizen or national of...

  7. 22 CFR 41.58 - Aliens in religious occupations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens in religious occupations. 41.58 Section... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.58 Aliens in religious occupations. (a) Requirements for “R” classification. An alien shall be classifiable under the provisions of...

  8. 8 CFR 1241.30 - Aliens ordered deported.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ordered deported, see 8 CFR 241.30 through 241.33. ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Aliens ordered deported. 1241.30 Section 1241.30 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  9. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  10. 8 CFR 1241.20 - Aliens ordered excluded.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., see 8 CFR 241.20 through 241.25. ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Aliens ordered excluded. 1241.20 Section 1241.20 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  11. 20 CFR 404.1036 - Certain nonresident aliens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Certain nonresident aliens. 404.1036 Section... Employment § 404.1036 Certain nonresident aliens. (a) Foreign students. (1) Foreign students (nonimmigrant aliens) may be temporarily in the United States under subparagraph (F) of section 101(a)(15) of...

  12. 32 CFR 1602.3 - Aliens and nationals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Aliens and nationals. 1602.3 Section 1602.3 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.3 Aliens and nationals. (a) The term alien means any person who is not a citizen or national of...

  13. 22 CFR 40.9 - Classes of inadmissible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to...

  14. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in...

  15. 22 CFR 41.55 - Aliens with extraordinary ability.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Aliens with extraordinary ability. 41.55... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.55 Aliens with extraordinary ability. (a) Requirements for O classification. An alien shall be classifiable under the provisions of INA...

  16. 8 CFR 1241.20 - Aliens ordered excluded.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., see 8 CFR 241.20 through 241.25. ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Aliens ordered excluded. 1241.20 Section 1241.20 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  17. Socio-economic Predictors of Alienation among the Elderly.

    ERIC Educational Resources Information Center

    Durant, Thomas J., Jr.; Christian, Ollie

    1990-01-01

    Studied level of alienation and associations between socioeconomic variables and alienation in 200 older senior center clients. Found group isolation and powerlessness were more prevalent than personal isolation or normlessness; health, race, education, and income were strongest predictors of alienation; and older Blacks and those with lower…

  18. 28 CFR 0.47 - Alien property matters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Alien property matters. 0.47 Section 0.47....47 Alien property matters. The Office of Alien Property shall be a part of the Civil Division: (a) The following described matters are assigned to, and shall be conducted, handled, or supervised by...

  19. 28 CFR 0.47 - Alien property matters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Alien property matters. 0.47 Section 0.47....47 Alien property matters. The Office of Alien Property shall be a part of the Civil Division: (a) The following described matters are assigned to, and shall be conducted, handled, or supervised by...

  20. 28 CFR 0.47 - Alien property matters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alien property matters. 0.47 Section 0.47....47 Alien property matters. The Office of Alien Property shall be a part of the Civil Division: (a) The following described matters are assigned to, and shall be conducted, handled, or supervised by...

  1. 28 CFR 0.47 - Alien property matters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Alien property matters. 0.47 Section 0.47....47 Alien property matters. The Office of Alien Property shall be a part of the Civil Division: (a) The following described matters are assigned to, and shall be conducted, handled, or supervised by...

  2. 8 CFR 1241.30 - Aliens ordered deported.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ordered deported, see 8 CFR 241.30 through 241.33. ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Aliens ordered deported. 1241.30 Section 1241.30 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  3. 20 CFR 404.1036 - Certain nonresident aliens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Certain nonresident aliens. 404.1036 Section... Employment § 404.1036 Certain nonresident aliens. (a) Foreign students. (1) Foreign students (nonimmigrant aliens) may be temporarily in the United States under subparagraph (F) of section 101(a)(15) of...

  4. 8 CFR 1241.20 - Aliens ordered excluded.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., see 8 CFR 241.20 through 241.25. ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Aliens ordered excluded. 1241.20 Section 1241.20 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF...

  5. 45 CFR 233.51 - Eligibility of sponsored aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 2 2014-10-01 2012-10-01 true Eligibility of sponsored aliens. 233.51 Section 233... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor...

  6. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in...

  7. 22 CFR 41.55 - Aliens with extraordinary ability.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Aliens with extraordinary ability. 41.55... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.55 Aliens with extraordinary ability. (a) Requirements for O classification. An alien shall be classifiable under the provisions of INA...

  8. 32 CFR 1630.46 - Class 4-T: Treaty alien.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Class 4-T: Treaty alien. 1630.46 Section 1630.46 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.46 Class 4-T: Treaty alien. In Class 4-T shall be placed any registrant who is an alien...

  9. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....1 of this chapter upon the person or persons specified by 8 CFR 103.8(c). (b) Service custody and... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION...

  10. 22 CFR 41.58 - Aliens in religious occupations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Aliens in religious occupations. 41.58 Section... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.58 Aliens in religious occupations. (a) Requirements for “R” classification. An alien shall be classifiable under the provisions of...

  11. 32 CFR 1602.3 - Aliens and nationals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Aliens and nationals. 1602.3 Section 1602.3 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.3 Aliens and nationals. (a) The term alien means any person who is not a citizen or national of...

  12. 22 CFR 40.9 - Classes of inadmissible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to...

  13. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart....

  14. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Coverage for certain aliens. 435.139 Section 435... ISLANDS, AND AMERICAN SAMOA Mandatory Coverage Mandatory Coverage of Certain Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency...

  15. 42 CFR 436.330 - Coverage for certain aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Coverage for certain aliens. 436.330 Section 436... Coverage of the Medically Needy § 436.330 Coverage for certain aliens. If an agency provides Medicaid to... condition, as defined in § 440.255(c) of this chapter to those aliens described in § 436.406(c) of...

  16. Systemic Disaffection: A Three-Factor Theory of Political Alienation.

    ERIC Educational Resources Information Center

    Long, Samuel

    The paper develops a theory of political alienation based upon interactions among three antecedent conditions. Political alienation is interpreted as combining feelings of inefficacy, discontent, cynicism, estrangement, and hopelessness. The factors evaluated for their contribution to political alienation are: (1) critical perceptions of…

  17. Alienation: A Concept for Understanding Low-Income, Urban Clients

    ERIC Educational Resources Information Center

    Holcomb-McCoy, Cheryl

    2004-01-01

    The author examines the concept of alienation and how it can be used to understand low-income, urban clients. A description is presented of 4 dimensions of alienation: powerlessness, meaninglessness, normlessness, and social isolation. Case illustrations are provided, and recommendations are made for counseling alienated clients. This article…

  18. Index of Alien Impact: A Method for Evaluating Potential Ecological Impact of Alien Plant Species

    NASA Astrophysics Data System (ADS)

    Magee, Teresa K.; Ringold, Paul L.; Bollman, Michael A.; Ernst, Ted L.

    2010-04-01

    Alien plant species are stressors to ecosystems and indicators of reduced ecosystem integrity. The magnitude of the stress reflects not only the quantity of aliens present, but also the quality of their interactions with native ecosystems. We develop an Index of Alien Impact ( IAI) to estimate the collective ecological impact of in situ alien species. IAI summarizes the frequency of occurrence and potential ecological impact ( Invasiveness-Impact Score ( I i )) of individual alien species for all aliens present in a particular location or community type. A component metric, I i , is based on ecological species traits (life history, ecological amplitude, and ability to alter ecosystem processes) that reflect mechanisms, which can increase impact to ecosystem structure and function. While I i is less complex than some other multi-metric rankings of alien impact, it compares well to these metrics and to qualitative judgments. IAI can be adapted for different ecological settings by modifying the set of species traits incorporated in I i to reflect properties likely to breach biotic and abiotic barriers or alter ecosystem function in a particular region or community type of interest. To demonstrate our approach, we created versions of IAI and I i , applicable to the diverse streamside vegetation of a river basin (19,631 km2) spanning low-elevation arid to mesic montane habitats in eastern Oregon, USA. In this demonstration effort, we (1) evaluate relationships of IAI to metrics describing invasion level, and (2) illustrate the potential utility of IAI for prioritizing alien species management activities and informing restoration goals.

  19. The Lonely Consumer: Advertising and Alienation.

    ERIC Educational Resources Information Center

    Larson, Charles U.; Denton, Robert E.

    Advertising plays on the broad feelings of alienation (defined as an individual's frustrated or estranged responses to economic and sociological phenomena which affect that individual's place in society) which are endemic to the American consumer society and are, in Marxist views, symptomatic of any capitalist system. By generating anxieties and…

  20. Pathophysiology and Treatment of Alien Hand Syndrome

    PubMed Central

    Sarva, Harini; Deik, Andres; Severt, William Lawrence

    2014-01-01

    Background Alien hand syndrome (AHS) is a disorder of involuntary, yet purposeful, hand movements that may be accompanied by agnosia, aphasia, weakness, or sensory loss. We herein review the most reported cases, current understanding of the pathophysiology, and treatments. Methods We performed a PubMed search in July of 2014 using the phrases “alien hand syndrome,” “alien hand syndrome pathophysiology,” “alien hand syndrome treatment,” and “anarchic hand syndrome.” The search yielded 141 papers (reviews, case reports, case series, and clinical studies), of which we reviewed 109. Non-English reports without English abstracts were excluded. Results Accumulating evidence indicates that there are three AHS variants: frontal, callosal, and posterior. Patients may demonstrate symptoms of multiple types; there is a lack of correlation between phenomenology and neuroimaging findings. Most pathologic and functional imaging studies suggest network disruption causing loss of inhibition as the likely cause. Successful interventions include botulinum toxin injections, clonazepam, visuospatial coaching techniques, distracting the affected hand, and cognitive behavioral therapy. Discussion The available literature suggests that overlap between AHS subtypes is common. The evidence for effective treatments remains anecdotal, and, given the rarity of AHS, the possibility of performing randomized, placebo-controlled trials seems unlikely. As with many other interventions for movement disorders, identifying the specific functional impairments caused by AHS may provide the best guidance towards individualized supportive care. PMID:25506043

  1. Aliens Among Us : Are They Already Here ?

    NASA Astrophysics Data System (ADS)

    McGaha, J.

    2008-03-01

    Popular culture, science fiction and mainstream belief, says they are! What is the evidence? Astronomer, skeptic and retired USAF pilot James McGaha examines this "Space Age" Mythology. From years of investigation of the physical evidence of aliens and there spacecraft (UFO's) here on earth, McGaha presents the scientific facts.

  2. Processes of Alienation: Marx, Orff and Kodaly

    ERIC Educational Resources Information Center

    Benedict, Cathy

    2009-01-01

    Using Marx as a lens through which to interrogate music methodology, in particular those espoused by Orff and Kodaly, this article suggests that rather than the free play and creativity Orff and Kodaly intended, the implementation of these methods in a strict and unmindful manner, often alienates both teacher and student from musicking. Thus these…

  3. College as a Source of Black Alienation.

    ERIC Educational Resources Information Center

    Shingles, Richard D.

    1979-01-01

    This article summarizes college and precollege explanations of alienation and indicates how they intertwine in the case of Black college students. A multivariate analysis of Black students is then used to control for precollege experiences and isolate the independent impact of college life on Black students at a predominantly White university.…

  4. Student Drug Usage and Self-Alienation.

    ERIC Educational Resources Information Center

    Fischler, Michael L.

    Utilizing responses (a self administered, 15 item questionnaire) of a rural northeastern New England sample of junior high, senior high, and college students, correlation between legal and illegal drug use and perceived self-alienation was examined. Comparison was also made between users and nonusers. Legal users were defined as those who made at…

  5. The Alienating Influence of the Illusionogens

    ERIC Educational Resources Information Center

    Malcolm, Andrew I.

    1971-01-01

    The author, based on his discussion, hypothesizes that: (1) the use of marijuana may serve to intensify the tendency toward an adolescent's alienation and (2) attitudinal changes do occur in people who are exposed to the illusionogens and that these changes are more certainly fixed with continued use. (Author/BY)

  6. Invite an Alien to Astronomy Night

    ERIC Educational Resources Information Center

    Governor, Donna; Richwine, Pebble

    2007-01-01

    Dozens of inflatable aliens recently "descended" upon the authors' middle school to kick-off their first school-wide Astronomy night. With an estimated attendance of over 500, their eighth-grade students hosted over a dozen activity-rich sessions designed to entertain and educate students and their families about the wonders of the solar system…

  7. Creating Aliens: The Ultimate Life Sciences Activity.

    ERIC Educational Resources Information Center

    Beltramo, Dan

    2001-01-01

    Describes a seven-week project completed by the author's eighth-grade science students (as they studied "the chemistry of living things") in which they designed an alien and its world using the scientific concepts that they learned in class. Compares class presentations using PowerPoint software to presentations using posterboard. (SR)

  8. Combatives for Alienated Youth: Problems and Prospects.

    ERIC Educational Resources Information Center

    Hellison, Don

    Combative activities (boxing, wrestling, kung fu, etc.) are seen as having a positive influence on alienated inner city youth. Potential contributions of such activities in a school curriculum or recreation program include involvement, security, self-concept, and self-realization. Participants may be able to free themselves from such stereotype…

  9. 22 CFR 62.27 - Alien physicians.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... or academic medical center which has been designated an exchange visitor program by the Secretary of... Relations DEPARTMENT OF STATE PUBLIC DIPLOMACY AND EXCHANGES EXCHANGE VISITOR PROGRAM Specific Program Provisions § 62.27 Alien physicians. (a) Purpose. Pursuant to the Mutual Educational and Cultural...

  10. 22 CFR 62.27 - Alien physicians.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... or academic medical center which has been designated an exchange visitor program by the Secretary of... Relations DEPARTMENT OF STATE PUBLIC DIPLOMACY AND EXCHANGES EXCHANGE VISITOR PROGRAM Specific Program Provisions § 62.27 Alien physicians. (a) Purpose. Pursuant to the Mutual Educational and Cultural...

  11. Alteration of wheat vernalization requirement by alien chromosome-mediated transposition of MITE.

    PubMed

    Gorafi, Yasir Serag Alnor; Eltayeb, Amin Elsadig; Tsujimoto, Hisashi

    2016-03-01

    Under the changing climate, early flowering is advantageous to escape terminal heat and drought. Previously during evaluation of 14 chromosome introgression lines (ILs), we found three ILs that flowered a month earlier than their wheat background Chinese Spring (CS). This paper describes the cause of the early flowering in the ILs and provides insight into the evolution of spring wheat from the winter wheat. We used specific molecular markers for Vrn genes to determine its allelic composition. Phenotypic evaluations carried out under field conditions and in a growth chamber. Unlike the winter vrn-A1 allele of CS, the spring Vrn-A1 allele of the ILs had insertions of 222 and 131-bp miniature inverted-repeat transposable element (MITE) in the promoter region. Sequence analysis indicated that the 222-bp insertion is similar to an insertion in the spring genotype, Triple Dirk D. Our results ruled out any possibility of outcrossing or contamination. Without vernalization, Vrn-A1 is highly expressed in the ILs compared to CS. We attribute the early flowering of the ILs to the insertion of the MITE in the promoter of Vrn-A1. The alien chromosome might mediate this insertion. PMID:27162490

  12. Alteration of wheat vernalization requirement by alien chromosome-mediated transposition of MITE

    PubMed Central

    Gorafi, Yasir Serag Alnor; Eltayeb, Amin Elsadig; Tsujimoto, Hisashi

    2016-01-01

    Under the changing climate, early flowering is advantageous to escape terminal heat and drought. Previously during evaluation of 14 chromosome introgression lines (ILs), we found three ILs that flowered a month earlier than their wheat background Chinese Spring (CS). This paper describes the cause of the early flowering in the ILs and provides insight into the evolution of spring wheat from the winter wheat. We used specific molecular markers for Vrn genes to determine its allelic composition. Phenotypic evaluations carried out under field conditions and in a growth chamber. Unlike the winter vrn-A1 allele of CS, the spring Vrn-A1 allele of the ILs had insertions of 222 and 131-bp miniature inverted-repeat transposable element (MITE) in the promoter region. Sequence analysis indicated that the 222-bp insertion is similar to an insertion in the spring genotype, Triple Dirk D. Our results ruled out any possibility of outcrossing or contamination. Without vernalization, Vrn-A1 is highly expressed in the ILs compared to CS. We attribute the early flowering of the ILs to the insertion of the MITE in the promoter of Vrn-A1. The alien chromosome might mediate this insertion. PMID:27162490

  13. Mobilization of the active MITE transposons mPing and Pong in rice by introgression from wild rice (Zizania latifolia Griseb.).

    PubMed

    Shan, Xiaohui; Liu, Zhenlan; Dong, Zhenying; Wang, Yongming; Chen, Yu; Lin, Xiuyun; Long, Likun; Han, Fangpu; Dong, Yingshan; Liu, Bao

    2005-04-01

    Hybridization between different species plays an important role in plant genome evolution, as well as is a widely used approach for crop improvement. McClintock has predicted that plant wide hybridization constitutes a "genomic shock" whereby cryptic transposable elements may be activated. However, direct experimental evidence showing a causal relationship between plant wide hybridization and transposon mobilization has not yet been reported. The miniature-Ping (mPing) is a recently isolated active miniature inverted-repeat transposable element transposon from rice, which is mobilized by tissue culture and gamma-ray irradiation. We show herein that mPing, together with its putative transposase-encoding partner, Pong, is mobilized in three homologous recombinant inbred lines (RILs), derived from hybridization between rice (cultivar Matsumae) and wild rice (Zizania latifolia Griseb.), harboring introgressed genomic DNA from wild rice. In contrast, both elements remain immobile in two lines sharing the same parentage to the RILs but possessing no introgressed DNA. Thus, we have presented direct evidence that is consistent with McClintock's insight by demonstrating a causal link between wide hybridization and transposon mobilization in rice. In addition, we report an atypical behavior of mPing/Pong mobilization in these lines, i.e., the exclusive absence of footprints after excision. PMID:15647520

  14. The Roles of Ecological and Evolutionary Processes in Plant Community Assembly: The Environment, Hybridization, and Introgression Influence Co-occurrence of Eucalyptus.

    PubMed

    Pollock, Laura J; Bayly, Michael J; Vesk, Peter A

    2015-06-01

    Introgressive hybridization is increasingly recognized as having influenced the gene pools of large genera of plants, yet it is rarely invoked as an explanation for why closely related plant species do not co-occur. Here, we asked how the environment and tendency to interbreed relate to neighborhood co-occurrence patterns for Eucalyptus species in the Grampians National Park, Victoria, Australia. We identified species pairs that have experienced ongoing hybridization and introgression on the basis of the extent of incongruence between chloroplast DNA (JLA+ region) and nuclear ribosomal DNA (internal transcribed spacer region) phylogenies, geographic patterns of gene sharing, and field observation of intermediate morphologies. Co-occurrence, trait data (specific leaf area [SLA], maximum height, and seed mass), and environmental data were measured in plots distributed along environmental gradients. Trait and habitat similarity influenced species co-occurrence the most overall (e.g., co-occurring species had similar SLA). Reproductively compatible species were an exception; they rarely co-occurred despite being functionally similar. The negative effect of reproductive compatibility was stronger than the positive effect of SLA on co-occurrence. Our results emphasize the dominant roles of the environment and the importance of evolution in structuring local assemblages. We argue that the mechanism responsible for preventing closely related species from co-occurring in this system is reproductive interference rather than competitive exclusion. Reproductive interference should be considered more generally as a potential cause of phylogenetic overdispersion. PMID:25996863

  15. Intentional genetic introgression influences survival of adults and subadults in a small, inbred felid population.

    PubMed

    Benson, John F; Hostetler, Jeffrey A; Onorato, David P; Johnson, Warren E; Roelke, Melody E; O'Brien, Stephen J; Jansen, Deborah; Oli, Madan K

    2011-09-01

    1. Inbreeding and low genetic diversity can cause reductions in individual fitness and increase extinction risk in animal populations. Intentional introgression, achieved by releasing genetically diverse individuals into inbred populations, has been used as a conservation tool to improve demographic performance in endangered populations. 2. By the 1980s, Florida panthers (Puma concolor coryi) had been reduced to a small, inbred population that appeared to be on the brink of extinction. In 1995, female pumas from Texas (P. c. stanleyana) were released in occupied panther range as part of an intentional introgression programme to restore genetic variability and improve demographic performance of panthers. 3. We used 25 years (1981-2006) of continuous radiotelemetry and genetic data to estimate and model subadult and adult panther survival and cause-specific mortality to provide rigorous sex and age class-specific survival estimates and evaluate the effect of the introgression programme on these parameters. 4. Genetic ancestry influenced annual survival of subadults and adults after introgression, as F(1) generation admixed panthers ( = 0·98) survived better than pre-introgression type panthers ( = 0·77) and other admixed individuals ( = 0·82). Furthermore, heterozygosity was higher for admixed panthers relative to pre-introgression type panthers and positively influenced survival. 5. Our results are consistent with hybrid vigour; however, extrinsic factors such as low density of males in some areas of panther range may also have contributed to higher survival of F(1) panthers. Regardless, improved survival of F(1) subadults and adults likely contributed to the numerical increase in panthers following introgression, and our results indicate that intentional admixture, achieved here by releasing individuals from another population, appears to have been successful in improving demographic performance in this highly endangered population. PMID:21338353

  16. Interspecific hybridization and mitochondrial introgression in invasive carcinus shore crabs.

    PubMed

    Darling, John A

    2011-01-01

    Interspecific hybridization plays an important role in facilitating adaptive evolutionary change. More specifically, recent studies have demonstrated that hybridization may dramatically influence the establishment, spread, and impact of invasive populations. In Japan, previous genetic evidence for the presence of two non-native congeners, the European green crab Carcinus maenas and the Mediterranean green crab C. aestuarii, has raised questions regarding the possibility of hybridization between these sister species. Here I present analysis based on both nuclear microsatellites and the mitochondrial cytochrome C oxidase subunit I (COI) gene which unambiguously argues for a hybrid origin of Japanese Carcinus. Despite the presence of mitochondrial lineages derived from both C. maenas and C. aestuarii, the Japanese population is panmictic at nuclear loci and has achieved cytonuclear equilibrium throughout the sampled range in Japan. Furthermore, analysis of admixture at nuclear loci indicates dramatic introgression of the C. maenas mitochondrial genome into a predominantly C. aestuarii nuclear background. These patterns, along with inferences drawn from the observational record, argue for a hybridization event pre-dating the arrival of Carcinus in Japan. The clarification of both invasion history and evolutionary history afforded by genetic analysis provides information that may be critically important to future studies aimed at assessing risks posed by invasive Carcinus populations to Japan and the surrounding region. PMID:21423759

  17. Production and identification of wheat - Agropyron cristatum (1.4P) alien translocation lines.

    PubMed

    Liu, Wei-Hua; Luan, Yang; Wang, Jing-Chang; Wang, Xiao-Guang; Su, Jun-Ji; Zhang, Jin-Peng; Yang, Xin-Ming; Gao, Ai-Nong; Li, Li-Hui

    2010-06-01

    The P genome of Agropyron Gaertn., a wild relative of wheat, contains an abundance of desirable genes that can be utilized as genetic resources to improve wheat. In this study, wheat - Aegilops cylindrica Host gametocidal chromosome 2C addition lines were crossed with wheat - Agropyron cristatum (L.) Gaertn. disomic addition line accession II-21 with alien recombinant chromosome (1.4)P. We successfully induced wheat - A. cristatum alien chromosomal translocations for the first time. The frequency of translocation in the progeny was 3.75%, which was detected by molecular markers and genomic in situ hybridization (GISH). The translocation chromosomes were identified by dual-color GISH /fluorescence in situ hybridization (FISH). The P genomic DNA was used as probe to detect the (1.4)P chromosome fragment, and pHvG39, pAs1, or pSc119.2 repeated sequences were used as probes to identify wheat translocated chromosomes. The results showed that six types of translocations were identified in the three wheat - A. cristatum alien translocation lines, including the whole arm or terminal portion of a (1.4)P chromosome. The (1.4)P chromosome fragments were translocated to wheat chromosomes 1B, 2B, 5B, and 3D. The breakpoints were located at the centromeres of 1B and 2B, the pericentric locations of 5BS, and the terminals of 5BL and 3DS. In addition, we obtained 12 addition-deletion lines that contained alien A. cristatum chromosome (1.4)P in wheat background. All of these wheat - A. cristatum alien translocation lines and addition-deletion lines would be valuable for identifying A. cristatum chromosome (1.4)P-related genes and providing genetic resources and new germplasm accessions for the genetic improvement of wheat. The specific molecular markers of A. cristatum (1.4)P chromosome have been developed and used to track the (1.4)P chromatin. PMID:20555436

  18. Reticulate evolutionary history and extensive introgression in mosquito species revealed by phylogenetic network analysis.

    PubMed

    Wen, Dingqiao; Yu, Yun; Hahn, Matthew W; Nakhleh, Luay

    2016-06-01

    The role of hybridization and subsequent introgression has been demonstrated in an increasing number of species. Recently, Fontaine et al. (Science, 347, 2015, 1258524) conducted a phylogenomic analysis of six members of the Anopheles gambiae species complex. Their analysis revealed a reticulate evolutionary history and pointed to extensive introgression on all four autosomal arms. The study further highlighted the complex evolutionary signals that the co-occurrence of incomplete lineage sorting (ILS) and introgression can give rise to in phylogenomic analyses. While tree-based methodologies were used in the study, phylogenetic networks provide a more natural model to capture reticulate evolutionary histories. In this work, we reanalyse the Anopheles data using a recently devised framework that combines the multispecies coalescent with phylogenetic networks. This framework allows us to capture ILS and introgression simultaneously, and forms the basis for statistical methods for inferring reticulate evolutionary histories. The new analysis reveals a phylogenetic network with multiple hybridization events, some of which differ from those reported in the original study. To elucidate the extent and patterns of introgression across the genome, we devise a new method that quantifies the use of reticulation branches in the phylogenetic network by each genomic region. Applying the method to the mosquito data set reveals the evolutionary history of all the chromosomes. This study highlights the utility of 'network thinking' and the new insights it can uncover, in particular in phylogenomic analyses of large data sets with extensive gene tree incongruence. PMID:26808290

  19. Genetic introgression and species boundary of two geographically overlapping pine species revealed by molecular markers.

    PubMed

    Zhang, Defang; Xia, Tao; Yan, Maomao; Dai, Xiaogang; Xu, Jin; Li, Shuxian; Yin, Tongming

    2014-01-01

    Gene introgression and hybrid barriers have long been a major focus of studies of geographically overlapping species. Two pine species, Pinus massoniana and P. hwangshanensis, are frequently observed growing adjacent to each other, where they overlap in a narrow hybrid zone. As a consequence, these species constitute an ideal system for studying genetic introgression and reproductive barriers between naturally hybridizing, adjacently distributed species. In this study, we sampled 270 pine trees along an elevation gradient in Anhui Province, China and analyzed these samples using EST-SSR markers. The molecular data revealed that direct gene flow between the two species was fairly low, and that the majority of gene introgression was intermediated by backcrossing. On the basis of empirical observation, the on-site distribution of pines was divided into a P. massoniana zone, a hybrid zone, and a P. hwangshanensis zone. STRUCTURE analysis revealed the existence of a distinct species boundary between the two pine species. The genetic boundary of the hybrid zone, on the other hand, was indistinct owing to intensive backcrossing with parental species. Compared with P. massoniana, P. hwangshanensis was found to backcross with the hybrids more intensively, consistent with the observation that morphological and anatomical characteristics of trees in the contact zone were biased towards P. hwangshanensis. The introgression ability of amplified alleles varied across species, with some being completely blocked from interspecific introgression. Our study has provided a living example to help explain the persistence of adjacently distributed species coexisting with their interfertile hybrids. PMID:24977711

  20. [Unidirectional Hybridization of Kaluga Acipenser dauricus Georgi, 1775 and Amur Sturgeon Acipenser schrenckii Brandt, 1869, Inferred from the Mitochondrial DNA Genotyping of Their Natural Hybrids].

    PubMed

    Shedko, S V; Shedko, M B

    2016-03-01

    In 2009 through 2011, among 730 individuals of kaluga and Amur sturgeon collected in the lower reaches of the Amur River and the Amursky Liman, 17 morphologically intermediate individuals (hybrids) with the body length of 56 to 202 cm (median, 81 cm) were identified, including 11 individuals (4.6%) found in 2009, three individuals (1.6%) found in 2010, and three individuals (1.1%), in 2011. In 16 hybrids 819 bp of the mtDNA control regions were sequences and 11 haplotypes were identified. Since all these haplotypes were from the mtDNA lineages of kaluga, it was concluded that hybridization occurred in one direction, kaluga (♀) x Amur sturgeon (♂). This asymmetry could be caused by the large difference in sizes of these species. Since the earlier examined morphologically typical Amur sturgeons showed the absence of alien haplotypes (Shedko, et al., 2015), the absence of the mtDNA introgression is claimed. This can be caused by low viability or sterility of the backcross females (kaluga (♀) x Amur sturgeon (♂)) x Amur sturgeon (♂). The samples of hybrids and typical kaluga individuals demonstrated no differences in the frequency spectra of the mtDNA haplotypes. However, haplotype and nucleotide diversity in the first sample was somewhat higher than in the second one (0.950 versus 0.927 and 0.0054 versus 0.0044, respectively). The data obtained will be useful for population monitoring of kaluga and Amur sturgeon, Amur River endemics, which are classified as critically endangered by the IUCN Red List of Threatened Species. PMID:27281853

  1. Helianthus annuus ssp. texanus has chloroplast DNA and nuclear ribosomal RNA genes of Helianthus debilis ssp. cucumerifolius.

    PubMed Central

    Rieseberg, L H; Beckstrom-Sternberg, S; Doan, K

    1990-01-01

    Heiser [Heiser, C. B. (1951) Evolution 5, 42-51] hypothesized that Helianthus annuus ssp. texanus was derived by the introduction of H. annuus into Texas and subsequent introgression of genes from Helianthus debilis ssp. cucumerifolius into H. annuus. Although often considered to be one of the best cases of introgression in plants, alternative hypotheses to introgression, such as convergence or the joint retention of the ancestral condition, could not be ruled out in the original study. To test for the occurrence of introgression we examined 14 populations of H. annuus ssp. texanus, 14 allopatric populations of H. annuus, and three populations of H. debilis ssp. cucumerifolius with reference to diagnostic chloroplast DNA and nuclear ribosomal DNA markers. Thirteen of the 14 populations of H. annuus ssp. texanus had chloroplast DNA and/or ribosomal DNA markers of H. debilis ssp. cucumerifolius. In contrast, no chloroplast DNA or ribosomal DNA markers of H. debilis ssp. cucumerifolius were found in the 14 allopatric populations of H. annuus. Our findings provide strong support, therefore, for the hypothesized introgressive origin of H. annuus ssp. texanus. PMID:11607056

  2. Genetic introgression and hybridization in Antillean freshwater turtles (Trachemys) revealed by coalescent analyses of mitochondrial and cloned nuclear markers.

    PubMed

    Parham, James F; Papenfuss, Theodore J; Dijk, Peter Paul van; Wilson, Byron S; Marte, Cristian; Schettino, Lourdes Rodriguez; Brian Simison, W

    2013-04-01

    Determining whether a conflict between gene trees and species trees represents incomplete lineage sorting (ILS) or hybridization involving native and/or invasive species has implications for reconstructing evolutionary relationships and guiding conservation decisions. Among vertebrates, turtles represent an exceptional case for exploring these issues because of the propensity for even distantly related lineages to hybridize. In this study we investigate a group of freshwater turtles (Trachemys) from a part of its range (the Greater Antilles) where it is purported to have undergone reticulation events from both natural and anthropogenic processes. We sequenced mtDNA for 83 samples, sequenced three nuDNA markers for 45 samples, and cloned 29 polymorphic sequences, to identify species boundaries, hybridization, and intergrade zones for Antillean Trachemys and nearby mainland populations. Initial coalescent analyses of phased nuclear alleles (using (*)BEAST) recovered a Bayesian species tree that strongly conflicted with the mtDNA phylogeny and traditional taxonomy, and appeared to be confounded by hybridization. Therefore, we undertook exploratory phylogenetic analyses of mismatched alleles from the "coestimated" gene trees (Heled and Drummond, 2010) in order to identify potential hybrid origins. The geography, morphology, and sampling context of most samples with potential introgressed alleles suggest hybridization over ILS. We identify contact zones between different species on Jamaica (T. decussata × T. terrapen), on Hispaniola (T. decorata × T. stejnegeri), and in Central America (T. emolli × T. venusta). We are unable to determine whether the distribution of T. decussata on Jamaica is natural or the result of prehistoric introduction by Native Americans. This uncertainty means that the conservation status of the Jamaican T. decussata populations and contact zone with T. terrapen are unresolved. Human-mediated dispersal events were more conclusively implicated

  3. Unexpected population genetic structure of European roe deer in Poland: an invasion of the mtDNA genome from Siberian roe deer.

    PubMed

    Matosiuk, Maciej; Borkowska, Anetta; Świsłocka, Magdalena; Mirski, Paweł; Borowski, Zbigniew; Krysiuk, Kamil; Danilkin, Aleksey A; Zvychaynaya, Elena Y; Saveljev, Alexander P; Ratkiewicz, Mirosław

    2014-05-01

    Introgressive hybridization is a widespread evolutionary phenomenon which may lead to increased allelic variation at selective neutral loci and to transfer of fitness-related traits to introgressed lineages. We inferred the population genetic structure of the European roe deer (Capreolus capreolus) in Poland from mitochondrial (CR and cyt b) and sex-linked markers (ZFX, SRY, DBY4 and DBY8). Analyses of CR mtDNA sequences from 452 individuals indicated widespread introgression of Siberian roe deer (C. pygargus) mtDNA in the European roe deer genome, 2000 km from the current distribution range of C. pygargus. Introgressed individuals constituted 16.6% of the deer studied. Nearly 75% of them possessed haplotypes belonging to the group which arose 23 kyr ago and have not been detected within the natural range of Siberian roe deer, indicating that majority of present introgression has ancient origin. Unlike the mtDNA results, sex-specific markers did not show signs of introgression. Species distribution modelling analyses suggested that C. pygargus could have extended its range as far west as Central Europe after last glacial maximum. The main hybridization event was probably associated with range expansion of the most abundant European roe deer lineage from western refugia and took place in Central Europe after the Younger Dryas (10.8-10.0 ka BP). Initially, introgressed mtDNA variants could have spread out on the wave of expansion through the mechanism of gene surfing, reaching high frequencies in European roe deer populations and leading to observed asymmetrical gene flow. Human-mediated introductions of C. pygargus had minimal effect on the extent of mtDNA introgression. PMID:24697866

  4. 8 CFR 241.21 - Stay of deportation of excluded alien.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Stay of deportation of excluded alien. 241.21 Section 241.21 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens (for Hearings...

  5. 8 CFR 241.24 - Notice to transportation line of alien's exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Notice to transportation line of alien's exclusion. 241.24 Section 241.24 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens (for...

  6. 8 CFR 241.21 - Stay of deportation of excluded alien.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Stay of deportation of excluded alien. 241.21 Section 241.21 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens (for Hearings...

  7. 8 CFR 241.21 - Stay of deportation of excluded alien.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Stay of deportation of excluded alien. 241.21 Section 241.21 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens (for Hearings...

  8. 8 CFR 241.21 - Stay of deportation of excluded alien.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Stay of deportation of excluded alien. 241.21 Section 241.21 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens (for Hearings...

  9. 8 CFR 241.21 - Stay of deportation of excluded alien.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Stay of deportation of excluded alien. 241.21 Section 241.21 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens (for Hearings...

  10. 45 CFR 1626.4 - Aliens eligible for assistance under anti-abuse laws.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Aliens eligible for assistance under anti-abuse... SERVICES CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.4 Aliens eligible for assistance... alien who is within one of the following categories: (i) An alien who has been battered or subjected...

  11. Unidirectional diploid-tetraploid introgression among British birch trees with shifting ranges shown by restriction site-associated markers.

    PubMed

    Zohren, Jasmin; Wang, Nian; Kardailsky, Igor; Borrell, James S; Joecker, Anika; Nichols, Richard A; Buggs, Richard J A

    2016-06-01

    Hybridization may lead to introgression of genes among species. Introgression may be bidirectional or unidirectional, depending on factors such as the demography of the hybridizing species, or the nature of reproductive barriers between them. Previous microsatellite studies suggested bidirectional introgression between diploid Betula nana (dwarf birch) and tetraploid B. pubescens (downy birch) and also between B. pubescens and diploid B. pendula (silver birch) in Britain. Here, we analyse introgression among these species using 51 237 variants in restriction site-associated (RAD) markers in 194 individuals, called with allele dosages in the tetraploids. In contrast to the microsatellite study, we found unidirectional introgression into B. pubescens from both of the diploid species. This pattern fits better with the expected nature of the reproductive barrier between diploids and tetraploids. As in the microsatellite study, introgression into B. pubescens showed clear clines with increasing introgression from B. nana in the north and from B. pendula in the south. Unlike B. pendula alleles, introgression of B. nana alleles was found far from the current area of sympatry or allopatry between B. nana and B. pubescens. This pattern fits a shifting zone of hybridization due to Holocene reduction in the range of B. nana and expansion in the range of B. pubescens. PMID:27065091

  12. Hybridization and Introgression in a Sympatric Pair of Oak Species (Fagaceae) Studied with Morphology and Chloroplast and Nuclear SSR Markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chloroplast and nuclear SSR markers and morphology were used to study hybridization and introgression between Quercus douglasii and Q. lobata, two sympatric oak species native to California. Chloroplast SSR markers provided strong evidence of gene exchange via ongoing introgression between these sp...

  13. Genome-specific introgression between wheat and its wild relative Aegilops triuncialis.

    PubMed

    Parisod, C; Definod, C; Sarr, A; Arrigo, N; Felber, F

    2013-01-01

    Introgression of sequences from crop species in wild relatives is of fundamental and practical concern. Here, we address gene flow between cultivated wheat and its widespread polyploid relative, Aegilops triuncialis, using 12 EST-SSR markers mapped on wheat chromosomes. The presence of wheat diagnostic alleles in natural populations of the barbed goatgrass growing in proximity to cultivated fields highlights that substantial gene flow occurred when both species coexisted. Furthermore, loci from the A subgenome of wheat were significantly less introgressed than sequences from other subgenomes, indicating differential introgression into Ae. triuncialis. Gene flow between such species sharing nonhomeologous chromosomes addresses the evolutionary outcomes of hybridization and may be important for efficient gene containment. PMID:23205963

  14. Autoimmunity vs. cancer: predator vs. alien?

    PubMed

    Berens, Christian; Lauber, Kirsten; Herrmann, Martin

    2013-08-01

    "The enemy of my enemy is my friend." According to this motto, the human protagonists in Paul W. S. Anderson's science-fiction movie "Alien vs. Predator" (2004) solidarize with a predator in order to fight the aliens. Can this ancient and simple logic be transferred to the field of oncology and cancer immunotherapy? Can we utilize mechanisms known from the context of autoimmunity to fight cancer? Here, we summarize immune cell-mediated detection of danger and damage, central and peripheral tolerance, immunoregulation and immune privilege--processes known to be deregulated in the context of autoimmunity. We discuss them with special regard towards their misusage by tumors and pathogens and how they might be instrumentalized in the context of anti-cancer immunotherapy. PMID:23706137

  15. Introgression from Domestic Goat Generated Variation at the Major Histocompatibility Complex of Alpine Ibex

    PubMed Central

    Grossen, Christine; Keller, Lukas; Biebach, Iris; Croll, Daniel

    2014-01-01

    The major histocompatibility complex (MHC) is a crucial component of the vertebrate immune system and shows extremely high levels of genetic polymorphism. The extraordinary genetic variation is thought to be ancient polymorphisms maintained by balancing selection. However, introgression from related species was recently proposed as an additional mechanism. Here we provide evidence for introgression at the MHC in Alpine ibex (Capra ibex ibex). At a usually very polymorphic MHC exon involved in pathogen recognition (DRB exon 2), Alpine ibex carried only two alleles. We found that one of these DRB alleles is identical to a DRB allele of domestic goats (Capra aegagrus hircus). We sequenced 2489 bp of the coding and non-coding regions of the DRB gene and found that Alpine ibex homozygous for the goat-type DRB exon 2 allele showed nearly identical sequences (99.8%) to a breed of domestic goats. Using Sanger and RAD sequencing, microsatellite and SNP chip data, we show that the chromosomal region containing the goat-type DRB allele has a signature of recent introgression in Alpine ibex. A region of approximately 750 kb including the DRB locus showed high rates of heterozygosity in individuals carrying one copy of the goat-type DRB allele. These individuals shared SNP alleles both with domestic goats and other Alpine ibex. In a survey of four Alpine ibex populations, we found that the region surrounding the DRB allele shows strong linkage disequilibria, strong sequence clustering and low diversity among haplotypes carrying the goat-type allele. Introgression at the MHC is likely adaptive and introgression critically increased MHC DRB diversity in the genetically impoverished Alpine ibex. Our finding contradicts the long-standing view that genetic variability at the MHC is solely a consequence of ancient trans-species polymorphism. Introgression is likely an underappreciated source of genetic diversity at the MHC and other loci under balancing selection. PMID:24945814

  16. Mapping the genomic architecture of adaptive traits with interspecific introgressive origin: a coalescent-based approach.

    PubMed

    Hejase, Hussein A; Liu, Kevin J

    2016-01-01

    Recent studies of eukaryotes including human and Neandertal, mice, and butterflies have highlighted the major role that interspecific introgression has played in adaptive trait evolution. A common question arises in each case: what is the genomic architecture of the introgressed traits? One common approach that can be used to address this question is association mapping, which looks for genotypic markers that have significant statistical association with a trait. It is well understood that sample relatedness can be a confounding factor in association mapping studies if not properly accounted for. Introgression and other evolutionary processes (e.g., incomplete lineage sorting) typically introduce variation among local genealogies, which can also differ from global sample structure measured across all genomic loci. In contrast, state-of-the-art association mapping methods assume fixed sample relatedness across the genome, which can lead to spurious inference. We therefore propose a new association mapping method called Coal-Map, which uses coalescent-based models to capture local genealogical variation alongside global sample structure. Using simulated and empirical data reflecting a range of evolutionary scenarios, we compare the performance of Coal-Map against EIGENSTRAT, a leading association mapping method in terms of its popularity, power, and type I error control. Our empirical data makes use of hundreds of mouse genomes for which adaptive interspecific introgression has recently been described. We found that Coal-Map's performance is comparable or better than EIGENSTRAT in terms of statistical power and false positive rate. Coal-Map's performance advantage was greatest on model conditions that most closely resembled empirically observed scenarios of adaptive introgression. These conditions had: (1) causal SNPs contained in one or a few introgressed genomic loci and (2) varying rates of gene flow - from high rates to very low rates where incomplete lineage

  17. Does genetic introgression improve female reproductive performance? A test on the endangered Florida panther.

    PubMed

    Hostetler, Jeffrey A; Onorato, David P; Bolker, Benjamin M; Johnson, Warren E; O'Brien, Stephen J; Jansen, Deborah; Oli, Madan K

    2012-01-01

    Genetic introgression has been suggested as a management tool for mitigating detrimental effects of inbreeding depression, but the role of introgression in species conservation has been controversial, partly because population-level impacts of genetic introgressions are not well understood. Concerns about potential inbreeding depression in the endangered Florida panther (Puma concolor coryi) led to the release of eight female Texas pumas (P. c. stanleyana) into the Florida panther population in 1995. We used long-term reproductive data (1995-2008) collected from 61 female Florida panthers to estimate and model reproduction probability (probability of producing a litter) and litter size, and to investigate the influence of intentional genetic introgression on these parameters. Overall, 6-month probability of reproduction (±1SE) was 0.232 ± 0.021 and average litter size was 2.60 ± 0.09. Although F(1) admixed females had a lower reproduction probability than females with other ancestries, this was most likely because kittens born to F(1) females survive better; consequently, these females are unavailable for breeding until kittens are independent. There was no evidence for the effect of ancestry on litter size or of heterozygosity on probability of reproduction or litter size. In contrast, earlier studies have shown that genetic introgression positively affected Florida panther survival. Our results, along with those of earlier studies, clearly suggest that genetic introgression can have differential effects on components of fitness and highlight the importance of examining multiple demographic parameters when evaluating the effects of management actions. PMID:21805300

  18. Analysis of B-genome chromosome introgression in interspecific hybrids of Brassica napus × B. carinata.

    PubMed

    Navabi, Zahra K; Stead, Kiersten E; Pires, J Chris; Xiong, Zhiyong; Sharpe, Andrew G; Parkin, Isobel A P; Rahman, M Habibur; Good, Allen G

    2011-03-01

    Brassica carinata, an allotetraploid with B and C genomes, has a number of traits that would be valuable to introgress into B. napus. Interspecific hybrids were created between B. carinata (BBCC) and B. napus (AACC), using an advanced backcross approach to identify and introgress traits of agronomic interest from the B. carinata genome and to study the genetic changes that occur during the introgression process. We mapped the B and C genomes of B. carinata with SSR markers and observed their introgression into B. napus through a number of backcross generations, focusing on a BC(3) and BC(3)S(1) sibling family. There was close colinearity between the C genomes of B. carinata and B. napus and we provide evidence that B. carinata C chromosomes pair and recombine normally with those of B. napus, suggesting that similar to other Brassica allotetraploids no major chromosomal rearrangements have taken place since the formation of B. carinata. There was no evidence of introgression of the B chromosomes into the A or C chromosomes of B. napus; instead they were inherited as whole linkage groups with the occasional loss of terminal segments and several of the B-genome chromosomes were retained across generations. Several BC(3)S(1) families were analyzed using SSR markers, genomic in situ hybridization (GISH) assays, and chromosome counts to study the inheritance of the B-genome chromosome(s) and their association with morphological traits. Our work provides an analysis of the behavior of chromosomes in an interspecific cross and reinforces the challenges of introgressing novel traits into crop plants. PMID:21196520

  19. Evolutionary objections to "alien design" models.

    NASA Astrophysics Data System (ADS)

    Coffey, E. J.

    A previous paper demonstrated that the principal supporters of SETI have ignored the biological and evolutionary consequences of a creature's body form. In fact, the supporting evidence they provide actually contradicts their view. The approach they employ is that of the engineer: the process of "designing" a hypothetical creature to a specification irrespective of biological or evolutionary considerations. The principal types of "alien designs" which have been employed shall be discussed, and the evolutionary objections to them given.

  20. Phylogeography of Silver Pheasant (Lophura nycthemera L.) across China: aggregate effects of refugia, introgression and riverine barriers.

    PubMed

    Dong, Lu; Heckel, Gerald; Liang, Wei; Zhang, Yanyun

    2013-06-01

    The role of Pleistocene glacial cycles in forming the contemporary genetic structure of organisms has been well studied in China with a particular focus on the Tibetan Plateau. However, China has a complex topography and diversity of local climates, and how glacial cycles may have shaped the subtropical and tropical biota of the region remains mostly unaddressed. To investigate the factors that affected the phylogeography and population history of a widely distributed and nondeciduous forest species, we analysed morphological characters, mitochondrial DNA sequences and nuclear microsatellite loci in the Silver Pheasant (Lophura nycthemera). In a pattern generally consistent with phenotypic clusters, but not nominal subspecies, deeply divergent mitochondrial lineages restricted to different geographic regions were detected. Coalescent simulations indicated that the time of main divergence events corresponded to major glacial periods in the Pleistocene and gene flow was only partially lowered by drainage barriers between some populations. Intraspecific cytonuclear discordance was revealed in mitochondrial lineages from Hainan Island and the Sichuan Basin with evidence of nuclear gene flow from neighbouring populations into the latter. Unexpectedly, hybridization was revealed in Yingjiang between the Silver Pheasant and Kalij Pheasant (Lophura leucomelanos) with wide genetic introgression at both the mtDNA and nuclear levels. Our results highlight a novel phylogeographic pattern in a subtropical area generated from the combined effects of climate oscillation, partial drainage barriers and interspecific hybridization. Cytonuclear discordance combined with morphological differentiation implies that complex historical factors shaped the divergence process in this biodiversity hot spot area of southern China. PMID:23692215

  1. Alien species as a driver of recent extinctions.

    PubMed

    Bellard, Céline; Cassey, Phillip; Blackburn, Tim M

    2016-02-01

    We assessed the prevalence of alien species as a driver of recent extinctions in five major taxa (plants, amphibians, reptiles, birds and mammals), using data from the IUCN Red List. Our results show that alien species are the second most common threat associated with species that have gone completely extinct from these taxa since AD 1500. Aliens are the most common threat associated with extinctions in three of the five taxa analysed, and for vertebrate extinctions overall. PMID:26888913

  2. 8 CFR 215.4 - Procedure in case of alien prevented from departing from the United States.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Procedure in case of alien prevented from... IMMIGRATION REGULATIONS CONTROLS OF ALIENS DEPARTING FROM THE UNITED STATES § 215.4 Procedure in case of alien prevented from departing from the United States. (a) Any alien, other than an enemy alien, whose...

  3. 8 CFR 215.4 - Procedure in case of alien prevented from departing from the United States.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Procedure in case of alien prevented from... IMMIGRATION REGULATIONS CONTROLS OF ALIENS DEPARTING FROM THE UNITED STATES § 215.4 Procedure in case of alien prevented from departing from the United States. (a) Any alien, other than an enemy alien, whose...

  4. Selection of Gossypium hirsutum genotypes for interspecific introgression from G. arboreum using ovule culture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ovule culture is one of the techniques currently used to introgress desirable traits from Gossypium arboreum germplasm into G. hirsutum cultivars. Twenty-six G. hirsutum breeding lines were used as female parents in crosses with five G. arboreum accessions to determine if the G. hirsutum parent inf...

  5. Rapid and Targeted Introgression of Genes into Popular Cultivars Using Marker-Assisted Background Selection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have optimized a marker-assisted background selection (MABS)-based gene introgression approach in wheat where 97% or more of a recurrent parent genome can be recovered in just two backcrosses (BCs). A four-step MABS method was developed based on ‘Plabsim’ computer simulations and wheat genome str...

  6. Evaluating the use of ABBA-BABA statistics to locate introgressed loci.

    PubMed

    Martin, Simon H; Davey, John W; Jiggins, Chris D

    2015-01-01

    Several methods have been proposed to test for introgression across genomes. One method tests for a genome-wide excess of shared derived alleles between taxa using Patterson's D statistic, but does not establish which loci show such an excess or whether the excess is due to introgression or ancestral population structure. Several recent studies have extended the use of D by applying the statistic to small genomic regions, rather than genome-wide. Here, we use simulations and whole-genome data from Heliconius butterflies to investigate the behavior of D in small genomic regions. We find that D is unreliable in this situation as it gives inflated values when effective population size is low, causing D outliers to cluster in genomic regions of reduced diversity. As an alternative, we propose a related statistic ƒ(d), a modified version of a statistic originally developed to estimate the genome-wide fraction of admixture. ƒ(d) is not subject to the same biases as D, and is better at identifying introgressed loci. Finally, we show that both D and ƒ(d) outliers tend to cluster in regions of low absolute divergence (d(XY)), which can confound a recently proposed test for differentiating introgression from shared ancestral variation at individual loci. PMID:25246699

  7. Evaluating the Use of ABBA–BABA Statistics to Locate Introgressed Loci

    PubMed Central

    Martin, Simon H.; Davey, John W.; Jiggins, Chris D.

    2015-01-01

    Several methods have been proposed to test for introgression across genomes. One method tests for a genome-wide excess of shared derived alleles between taxa using Patterson’s D statistic, but does not establish which loci show such an excess or whether the excess is due to introgression or ancestral population structure. Several recent studies have extended the use of D by applying the statistic to small genomic regions, rather than genome-wide. Here, we use simulations and whole-genome data from Heliconius butterflies to investigate the behavior of D in small genomic regions. We find that D is unreliable in this situation as it gives inflated values when effective population size is low, causing D outliers to cluster in genomic regions of reduced diversity. As an alternative, we propose a related statistic f^d, a modified version of a statistic originally developed to estimate the genome-wide fraction of admixture. f^d is not subject to the same biases as D, and is better at identifying introgressed loci. Finally, we show that both D and f^d outliers tend to cluster in regions of low absolute divergence (dXY), which can confound a recently proposed test for differentiating introgression from shared ancestral variation at individual loci. PMID:25246699

  8. Metabolic Profiling and Physiological Analysis of a Novel Rice Introgression Line with Broad Leaf Size

    PubMed Central

    Zhao, Xiuqin; Zhang, Guilian; Wang, Yun; Zhang, Fan; Wang, Wensheng; Zhang, Wenhao; Fu, Binying; Xu, Jianlong; Li, Zhikang

    2015-01-01

    A rice introgression line, NIL-SS1, and its recurrent parent, Teqing, were used to investigate the influence of the introgression segment on plant growth. The current research showed NIL-SS1 had an increased flag leaf width, total leaf area, spikelet number per panicle and grain yield, but a decreased photosynthetic rate. The metabolite differences in NIL-SS1 and Teqing at different developmental stages were assessed using gas chromatography—mass spectrometry technology. Significant metabolite differences were observed across the different stages. NIL-SS1 increased the plant leaf nitrogen content, and the greatest differences between NIL-SS1 and Teqing occurred at the booting stage. Compared to Teqing, the metabolic phenotype of NIL-SS1 at the booting stage has closer association with those at the flowering stage. The introgression segment induced more active competition for sugars and organic acids (OAs) from leaves to the growing young spikes, which resulted in more spikelet number per plant (SNP). The results indicated the introgression segment could improve rice grain yield by increasing the SNP and total leaf area per plant, which resulted from the higher plant nitrogen content across growth stages and stronger competition for sugars and OAs of young spikes at the booting stage. PMID:26713754

  9. Introgression of root-knot nematode (RKN) resistance into tetraploid cottons.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The introgression of root-knot nematode (RKN) resistance into tetraploid cotton (Gossypium ssp.) and its ancestral genome origin were examined. Three major germplasm sources (Acala NemX, Clevewilt 6, and Auburn 623 RNR) of RKN resistance were compared with diverse germplasm using selected SSR marker...

  10. Metabolic Profiling and Physiological Analysis of a Novel Rice Introgression Line with Broad Leaf Size.

    PubMed

    Zhao, Xiuqin; Zhang, Guilian; Wang, Yun; Zhang, Fan; Wang, Wensheng; Zhang, Wenhao; Fu, Binying; Xu, Jianlong; Li, Zhikang

    2015-01-01

    A rice introgression line, NIL-SS1, and its recurrent parent, Teqing, were used to investigate the influence of the introgression segment on plant growth. The current research showed NIL-SS1 had an increased flag leaf width, total leaf area, spikelet number per panicle and grain yield, but a decreased photosynthetic rate. The metabolite differences in NIL-SS1 and Teqing at different developmental stages were assessed using gas chromatography-mass spectrometry technology. Significant metabolite differences were observed across the different stages. NIL-SS1 increased the plant leaf nitrogen content, and the greatest differences between NIL-SS1 and Teqing occurred at the booting stage. Compared to Teqing, the metabolic phenotype of NIL-SS1 at the booting stage has closer association with those at the flowering stage. The introgression segment induced more active competition for sugars and organic acids (OAs) from leaves to the growing young spikes, which resulted in more spikelet number per plant (SNP). The results indicated the introgression segment could improve rice grain yield by increasing the SNP and total leaf area per plant, which resulted from the higher plant nitrogen content across growth stages and stronger competition for sugars and OAs of young spikes at the booting stage. PMID:26713754

  11. Adaptive introgression of anticoagulant rodent poison resistance by hybridization between Old World mice

    PubMed Central

    Song, Ying; Endepols, Stefan; Klemann, Nicole; Richter, Dania; Matuschka, Franz-Rainer; Shih, Ching-Hua; Nachman, Michael W.; Kohn, Michael H.

    2011-01-01

    Summary It is known that evolution by selection on new or standing single nucleotide polymorphisms (SNPs) in the vitamin K 2,3-epoxide reductase subcomponent 1 (vkorc1) of house mice (Mus musculus domesticus) can cause resistance to anticoagulant rodenticides such as warfarin [1–3]. Here we report an introgression in European M. m. domesticus spanning as much as ~20.3 megabases (Mb) and including vkorc1, the molecular target of anticoagulants [1–4], that stems from hybridization with the Algerian mouse (M. spretus). We show that in the laboratory the homozygous complete vkorc1 allele of M. spretus confers resistance when introgressed into M. m. domesticus. Consistent with selection on the introgression after the introduction of rodenticides in the 1950s we document historically adaptive population genetics of vkorc1 in M. m. domesticus. Furthermore, we detected adaptive protein evolution of vkorc1 in the M. spretus lineage (Ka/Ks=1.54–1.93) resulting in radical amino-acid substitutions that apparently have anticoagulant tolerance of M. spretus as pleiotropic effect. Thus, positive selection produced an adaptive, divergent and pleiotropic vkorc1 allele in the donor species, M. spretus, which crossed a species barrier where it is expressed as adaptive trait in the recipient species, M. m. domesticus. Resistant house mice originated from selection on new or standing vkorc1 polymorphisms and from selection on vkorc1 polymorphisms acquired by adaptive introgressive hybridization. PMID:21782438

  12. Revisiting a classic case of introgression: hybridization and gene flow in Californian sunflowers.

    PubMed

    Owens, Gregory L; Baute, Gregory J; Rieseberg, Loren H

    2016-06-01

    During invasion, colonizing species can hybridize with native species, potentially swamping out native genomes. However, theory predicts that introgression will often be biased into the invading species. Thus, empirical estimates of gene flow between native and invasive species are important to quantify the actual threat of hybridization with invasive species. One classic example of introgression occurs in California, where Helianthus bolanderi was thought to be a hybrid between the serpentine endemic Helianthus exilis and the congeneric invader Helianthus annuus. We used genotyping by sequencing to look for signals of introgression and population structure. We find that H. bolanderi and H. exilis form one genetic clade, with weak population structure that is associated with geographic location rather than soil composition and likely represent a single species, not two. Additionally, while our results confirmed early molecular analysis and failed to support the hybrid origin of H. bolanderi, we did find evidence for introgression mainly into the invader H. annuus, as predicted by theory. PMID:26840428

  13. Analysis of wild-species introgressions in tomato inbreds uncovers ancestral origins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decades of intensive tomato breeding using wild germplasm has resulted in genomes of domesticated accessions (Solanum lycopersicum) to be intertwined with introgressions from their wild relatives. Here we present the first whole genome sequences of two tomato inbreds Gh13 and BTI87, both carrying a ...

  14. Neppiness in an Introgressed Population of Cotton: Genotypic Variation and Genotypic Correlation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Neps and seed coat fragments are two types of impurities in ginned fibers causing severe problems in textile processing during spinning and dyeing. The study was designed to investigate the genotypic variation for neps and seed coat fragments remaining in ginned fibers in an introgressed population ...

  15. Differential introgression in a mosaic hybrid zone reveals candidate barrier genes.

    PubMed

    Larson, Erica L; Andrés, Jose A; Bogdanowicz, Steven M; Harrison, Richard G

    2013-12-01

    Hybrid zones act as genomic sieves. Although globally advantageous alleles will spread throughout the zone and neutral alleles can be freely exchanged between species, introgression will be restricted for genes that contribute to reproductive barriers or local adaptation. Seminal fluid proteins (SFPs) are known to contribute to reproductive barriers in insects and have been proposed as candidate barrier genes in the hybridizing field crickets Gryllus pennsylvanicus and Gryllus firmus. Here, we have used 125 single nucleotide polymorphisms to characterize patterns of differential introgression and to identify genes that may contribute to prezygotic barriers between these species. Using a transcriptome scan of the male cricket accessory gland (the site of SFP synthesis), we identified genes with major allele frequency differences between the species. We then compared patterns of introgression for genes encoding SFPs with patterns for genes expressed in the same tissue that do not encode SFPs. We find no evidence that SFPs have reduced gene exchange across the cricket hybrid zone. However, a number of genes exhibit dramatically reduced introgression, and many of these genes encode proteins with functional roles consistent with known barriers. PMID:24299416

  16. Hybridization following recent secondary contact results in asymmetric genotypic and phenotypic introgression between island species of Myzomela honeyeaters.

    PubMed

    Sardell, Jason M; Uy, J Albert C

    2016-02-01

    Hybridization and introgression can have important evolutionary consequences for speciation, especially during early stages of secondary contact when reproductive barriers may be weak. Few studies, however, have quantified dynamics of hybridization and introgression in systems in which recent natural dispersal across a geographic barrier resulted in secondary contact. We investigated patterns of hybridization and introgression between two Myzomela honeyeaters (M. tristrami and M. cardinalis) that recently achieved secondary contact on Makira in the Solomon Islands. Hybridization in this system was hypothesized to be a byproduct of conspecific mate scarcity during early stages of colonization. Our research, however, provides evidence of ongoing hybridization more than a century after secondary contact. Mitochondrial sequencing revealed strongly asymmetric reproductive isolation that is most likely driven by postzygotic incompatibilities rather than prezygotic behavioral barriers. Nuclear introgression was observed from the native species (M. tristrami) to the colonizing species (M. cardinalis). Nuclear introgression in the reverse direction is almost exclusively limited to birds that are phenotypically M. tristrami but possess M. cardinalis mitochondrial haplotypes, consistent with introgression of plumage-related alleles into the genomic background of M. cardinalis. These results provide unique insight into the dynamics and consequences of hybridization and introgression during early stages of secondary contact. PMID:26787267

  17. Reindeer introgression and the population genetics of caribou in southwestern Alaska.

    PubMed

    Colson, Kevin E; Mager, Karen H; Hundertmark, Kris J

    2014-01-01

    Alaska caribou (Rangifer tarandus granti) in southwestern Alaska are a poorly understood system, with differing descriptions of their regional population structure, population abundance that has varied greatly through time and instances of the release of domestic reindeer (R. t. tarandus) into their range. Here, we use 21 microsatellites and 297 individuals to investigate the genetic population structure of herds and examine for population bottlenecks. Then, using genetic characteristics of existing reindeer populations, we examine introgression into the wild caribou populations. Caribou of the area are genetically diverse (H E between 0.69 and 0.84), with diversity decreasing along the Alaska Peninsula (AP). Using G ST and Jost's D, we find extensive structuring among all herds; Migrate-n finds that AP herds share few effective migrants with other herds, with Southern AP and Unimak Island herds having the least. Bayesian clustering techniques are able to resolve all but Denali and Mulchatna caribou herds. Using a conservative assignment threshold of q reindeer ≥ 0.2, 3% of caribou show signs of domestic introgression. Denali herd has the most introgressed individuals (6.9%); those caribou herds that were historically adjacent to smaller reindeer herds, or were historically without adjacent herding, show no admixture. This domestic introgression persists despite the lack of managed reindeer in the region since the 1940s. Our results suggest that despite previous movement data indicating metapopulation-like dispersal in this region, there may be unknown barriers to reproduction by dispersing individuals. Finally, our results support findings that wild and domestic Rangifer can hybridize and show this introgression may persist dozens of generations after domestics are no longer present. PMID:24842565

  18. Reticulate Speciation and Barriers to Introgression in the Anopheles gambiae Species Complex.

    PubMed

    Crawford, Jacob E; Riehle, Michelle M; Guelbeogo, Wamdaogo M; Gneme, Awa; Sagnon, N'Fale; Vernick, Kenneth D; Nielsen, Rasmus; Lazzaro, Brian P

    2015-11-01

    Speciation as a process remains a central focus of evolutionary biology, but our understanding of the genomic architecture and prevalence of speciation in the face of gene flow remains incomplete. The Anopheles gambiae species complex of malaria mosquitoes is a radiation of ecologically diverse taxa. This complex is well-suited for testing for evidence of a speciation continuum and genomic barriers to introgression because its members exhibit partially overlapping geographic distributions as well as varying levels of divergence and reproductive isolation. We sequenced 20 genomes from wild A. gambiae s.s., Anopheles coluzzii, Anopheles arabiensis, and compared these with 12 genomes from the "GOUNDRY" subgroup of A. gambiae s.l. Amidst a backdrop of strong reproductive isolation, we find strong evidence for a speciation continuum with introgression of autosomal chromosomal regions among species and subgroups. The X chromosome, however, is strongly differentiated among all taxa, pointing to a disproportionately large effect of X chromosome genes in driving speciation among anophelines. Strikingly, we find that autosomal introgression has occurred from contemporary hybridization between A. gambiae and A. arabiensis despite strong divergence (∼5× higher than autosomal divergence) and isolation on the X chromosome. In addition to the X, we find strong evidence that lowly recombining autosomal regions, especially pericentromeric regions, serve as barriers to introgression secondarily to the X. We show that speciation with gene flow results in genomic mosaicism of divergence and introgression. Such a reticulate gene pool connecting vector taxa across the speciation continuum has important implications for malaria control efforts. PMID:26615027

  19. Reticulate Speciation and Barriers to Introgression in the Anopheles gambiae Species Complex

    PubMed Central

    Crawford, Jacob E.; Riehle, Michelle M.; Guelbeogo, Wamdaogo M.; Gneme, Awa; Sagnon, N'Fale; Vernick, Kenneth D.; Nielsen, Rasmus; Lazzaro, Brian P.

    2015-01-01

    Speciation as a process remains a central focus of evolutionary biology, but our understanding of the genomic architecture and prevalence of speciation in the face of gene flow remains incomplete. The Anopheles gambiae species complex of malaria mosquitoes is a radiation of ecologically diverse taxa. This complex is well-suited for testing for evidence of a speciation continuum and genomic barriers to introgression because its members exhibit partially overlapping geographic distributions as well as varying levels of divergence and reproductive isolation. We sequenced 20 genomes from wild A. gambiae s.s., Anopheles coluzzii, Anopheles arabiensis, and compared these with 12 genomes from the “GOUNDRY” subgroup of A. gambiae s.l. Amidst a backdrop of strong reproductive isolation, we find strong evidence for a speciation continuum with introgression of autosomal chromosomal regions among species and subgroups. The X chromosome, however, is strongly differentiated among all taxa, pointing to a disproportionately large effect of X chromosome genes in driving speciation among anophelines. Strikingly, we find that autosomal introgression has occurred from contemporary hybridization between A. gambiae and A. arabiensis despite strong divergence (∼5× higher than autosomal divergence) and isolation on the X chromosome. In addition to the X, we find strong evidence that lowly recombining autosomal regions, especially pericentromeric regions, serve as barriers to introgression secondarily to the X. We show that speciation with gene flow results in genomic mosaicism of divergence and introgression. Such a reticulate gene pool connecting vector taxa across the speciation continuum has important implications for malaria control efforts. PMID:26615027

  20. Chemistry, life, and the search for aliens

    NASA Astrophysics Data System (ADS)

    Benner, Steven A.

    2010-09-01

    While "life" may universally be a self-sustaining chemical system capable of Darwinian evolution, alien life may be quite different in its chemistry from the terran life that we know here on Earth. In this case, it will be difficult to recognize, especially if it has not advanced beyond the single cell life forms that have dominated much of the terran biosphere. This review summarizes what we might infer from general physical and chemical law about how such "weird" life might be structured, what solvents other than water it might inhabit, what genetic molecules it might contain, and what metabolism it might exploit.

  1. Work alienation and problem alcohol behavior.

    PubMed

    Greenberg, E S; Grunberg, L

    1995-03-01

    Using a sample of production workers from union, nonunion, producer cooperative, and employee stock ownership plan (ESOP) wood products mills in the Northwest, we test the general proposition that work alienation, defined as low job autonomy, low use of capacities, and lack of participation in decision-making in the workplace, is associated with heavy drinking and negative consequences from drinking. We find that the general proposition is supported, but that the pathways tend to be indirect rather than direct, mediated by feelings of job satisfaction and respondents' beliefs about the utility of drinking as a means of coping. PMID:7738330

  2. 8 CFR 204.6 - Petitions for employment creation aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Commissioner for Examinations as provided in 8 CFR 103.3. (7) Requirements for alien entrepreneurs. An alien... this manner does not exempt the petitioner from the requirements of 8 CFR 204.6(j) (2) and (3) relating... meet the criteria set forth in 8 CFR 204.6(j)(4)(ii). (i) State designation of a high unemployment...

  3. 42 CFR 435.350 - Coverage for certain aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Coverage for certain aliens. 435.350 Section 435... ISLANDS, AND AMERICAN SAMOA Optional Coverage of the Medically Needy § 435.350 Coverage for certain aliens... treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  4. Widespread plant species: natives vs. aliens in our changing world

    USGS Publications Warehouse

    Stohlgren, Thomas J.; Pyšek, Petr; Kartesz, John; Nishino, Misako; Pauchard, Aníbal; Winter, Marten; Pino, Joan; Richardson, David M.; Wilson, John R.U.; Murray, Brad R.; Phillips, Megan L.; Ming-yang, Li; Celesti-Grapow, Laura; Font, Xavier

    2011-01-01

    Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However, alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level of invasion for several regions of the world in terms of the most widely distributed plant species (natives vs. aliens). Aliens accounted for 51.3% of the 120 most widely distributed plant species in North America, 43.3% in New South Wales (Australia), 34.2% in Chile, 29.7% in Argentina, and 22.5% in the Republic of South Africa. However, Europe had only 1% of alien species among the most widespread species of the flora. Across regions, alien species relative to native species were either as well-distributed (10 comparisons) or more widely distributed (5 comparisons). These striking patterns highlight the profound contribution that widespread invasive alien plants make to floristic dominance patterns across different regions. Many of the most widespread species are alien plants, and, in particular, Europe and Asia appear as major contributors to the homogenization of the floras in the Americas. We recommend that spatial extent of invasion should be explicitly incorporated in assessments of invasibility, globalization, and risk assessments.

  5. Widespread plant species: Natives versus aliens in our changing world

    USGS Publications Warehouse

    Stohlgren, T.J.; Pysek, P.; Kartesz, J.; Nishino, M.; Pauchard, A.; Winter, M.; Pino, J.; Richardson, D.M.; Wilson, J.R.U.; Murray, B.R.; Phillips, M.L.; Ming-yang, L.; Celesti-Grapow, L.; Font, X.

    2011-01-01

    Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However, alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level of invasion for several regions of the world in terms of the most widely distributed plant species (natives vs. aliens). Aliens accounted for 51.3% of the 120 most widely distributed plant species in North America, 43.3% in New South Wales (Australia), 34.2% in Chile, 29.7% in Argentina, and 22.5% in the Republic of South Africa. However, Europe had only 1% of alien species among the most widespread species of the flora. Across regions, alien species relative to native species were either as well-distributed (10 comparisons) or more widely distributed (5 comparisons). These striking patterns highlight the profound contribution that widespread invasive alien plants make to floristic dominance patterns across different regions. Many of the most widespread species are alien plants, and, in particular, Europe and Asia appear as major contributors to the homogenization of the floras in the Americas. We recommend that spatial extent of invasion should be explicitly incorporated in assessments of invasibility, globalization, and risk assessments. ?? 2011 Springer Science+Business Media B.V.

  6. 8 CFR 235.3 - Inadmissible aliens and expedited removal.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... asylum officer in accordance with 8 CFR 208.30. The examining immigration officer shall record sufficient... the United States in accordance with section 241(c) of the Act and 8 CFR part 241. (9) Waivers of... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Inadmissible aliens and expedited...

  7. 42 CFR 435.350 - Coverage for certain aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Coverage for certain aliens. 435.350 Section 435... ISLANDS, AND AMERICAN SAMOA Optional Coverage of the Medically Needy § 435.350 Coverage for certain aliens... treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  8. 42 CFR 435.350 - Coverage for certain aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Coverage for certain aliens. 435.350 Section 435... ISLANDS, AND AMERICAN SAMOA Optional Coverage of the Medically Needy § 435.350 Coverage for certain aliens... treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  9. 42 CFR 435.350 - Coverage for certain aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain aliens. 435.350 Section 435... ISLANDS, AND AMERICAN SAMOA Optional Coverage of the Medically Needy § 435.350 Coverage for certain aliens... treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  10. 8 CFR 235.3 - Inadmissible aliens and expedited removal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... asylum officer in accordance with 8 CFR 208.30. The examining immigration officer shall record sufficient... the United States in accordance with section 241(c) of the Act and 8 CFR part 241. (9) Waivers of... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Inadmissible aliens and expedited...

  11. Making Marx Accessible: Understanding Alienated Labor through Experiential Learning

    ERIC Educational Resources Information Center

    Parrotta, Kylie L.; Buck, Alison R.

    2013-01-01

    We introduce an exercise designed to make Marx's theory of alienated labor accessible to students in a Sociology of Work class. Through a role-playing activity where students create and sell goods under conditions of both alienated and nonalienated labor, students actually experience the different material and social consequences of these…

  12. Teaching English as a Second Language to Incarcerated Aliens.

    ERIC Educational Resources Information Center

    Edelson, Adelaide

    A study of the status of the instruction of incarcerated aliens in English as a second language (ESL) was undertaken to learn what is known about the subject and to determine whether incarcerated aliens have unique learning problems associated with their status as foreign nationals. Information was gathered through interviews with professionals in…

  13. Undocumented Aliens and the Nation's Two-Year Colleges.

    ERIC Educational Resources Information Center

    Smith, Milton L.

    In fall 1984, a nationwide study was conducted to determine the impact of undocumented aliens on two-year colleges. Surveys were mailed to presidents of 1,195 two-year colleges, requesting information on the number of undocumented aliens currently enrolled at the colleges, their nations of origin, their admission status, special modifications or…

  14. 7 CFR 273.4 - Citizenship and alien status.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... residing in the same household as the alien at the time of the abuse, an alien whose child has been... unmarried dependent child of such Hmong or Highland Laotian who is under the age of 18 or if a full-time student under the age of 22; an unmarried child under the age of 18 or if a full time student under...

  15. 22 CFR 41.24 - International organization aliens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false International organization aliens. 41.24... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Foreign Government Officials § 41.24 International organization aliens. (a) Definition of international organization. “International organization” means: (1) Any...

  16. 22 CFR 41.24 - International organization aliens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false International organization aliens. 41.24... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Foreign Government Officials § 41.24 International organization aliens. (a) Definition of international organization. “International organization” means: (1) Any...

  17. 22 CFR 41.24 - International organization aliens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false International organization aliens. 41.24... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Foreign Government Officials § 41.24 International organization aliens. (a) Definition of international organization. “International organization” means: (1) Any...

  18. 22 CFR 41.24 - International organization aliens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false International organization aliens. 41.24... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Foreign Government Officials § 41.24 International organization aliens. (a) Definition of international organization. “International organization” means: (1) Any...

  19. 22 CFR 41.24 - International organization aliens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false International organization aliens. 41.24... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Foreign Government Officials § 41.24 International organization aliens. (a) Definition of international organization. “International organization” means: (1) Any...

  20. 42 CFR 435.350 - Coverage for certain aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Coverage for certain aliens. 435.350 Section 435... ISLANDS, AND AMERICAN SAMOA Optional Coverage of the Medically Needy § 435.350 Coverage for certain aliens... treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  1. Political Disenchantment: A Cognitive-Perceptual Theory of Political Alienation.

    ERIC Educational Resources Information Center

    Long, Samuel

    An investigation of a cognitive-perceptual model to measure adolescents' feelings of political alienation is reported. The model hypothesizes that fundamental to the political alienation process is a feared actual or potential loss of freedom; this process is called psychological reactance. The sample consisted of 460 senior high school students…

  2. Alienation and Depression in the Small Town Widow.

    ERIC Educational Resources Information Center

    Jolley, Janina M.

    Research has found that elderly widows are alienated, disengaged, and depressed. However, there is little consensus across theories as to the inter-relationship of these variables. The social interactionist theory that disengagement leads to chronic depression and alienation was tested for a group of widows (N=32) and married women (N=28) over the…

  3. 26 CFR 301.7701(b)-1 - Resident alien.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Resident alien. 301.7701(b)-1 Section 301.7701(b)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) PROCEDURE AND ADMINISTRATION PROCEDURE AND ADMINISTRATION Definitions § 301.7701(b)-1 Resident alien. (a) Scope. Section 301.7701(b)-1(b) provides rules...

  4. Alienation in Physical Education from the Perspectives of Children

    ERIC Educational Resources Information Center

    Spencer-Cavaliere, Nancy; Rintoul, Mary Ann

    2012-01-01

    The purpose of this exploratory study was to examine the phenomenon of alienation in physical education from the perspectives of children. Of particular interest were children's perspectives about the three constructs of alienation: (a) powerlessness, (b) meaninglessness, and (c) social isolation, as defined by Carlson (1995). A case study…

  5. [Effect of an introgression from Aegilops cylindrica host on manifestation of productivity traits in winter common wheat F2 plants].

    PubMed

    Kozub, N A; Sozinov, I A; sozinov, A A

    2004-12-01

    The effect of introgression of a chromosome 1D segment from Aegilops cylindrica to winter common wheat on productivity traits in F2 plants was studied using storage protein loci as genetic markers. An allele of the gliadin-coding Gli-D1 locus served as a marker of the introgression. Using of two- and three-locus interaction models, it was shown that the introgression tagged with Gli-D1 affected the manifestation of productivity traits (productive tillering, grain weight per plant and grain number per plant) through interaction with other marker storage protein loci: Glu-B1, Glu-D1, and Gli-B2. PMID:15648149

  6. Parental alienation, DSM-5, and ICD-11: response to critics.

    PubMed

    Bernet, William; Baker, Amy J L

    2013-01-01

    There has been considerable interest among forensic practitioners in the proposals that parental alienation be included in the next editions of the Diagnostic and Statistical Manual of Mental Diseases (DSM) and The International Classification of Diseases (ICD). However, there has also been a great deal of misunderstanding about the proposals, and misinformation has been expressed in professional meetings, on websites, and in journal articles. In this article we address four common misunderstandings regarding parental alienation: that there is a lack of research to support it as a diagnosis; that adopting parental alienation as a diagnosis will lead to serious adverse consequences; that the advocates of parental alienation are driven by self-serving or malevolent motives; and that Richard Gardner should be criticized for self-publishing his description of parental alienation syndrome. PMID:23503183

  7. Evaluation of genetic introgression from domesticated pigs into the Ryukyu wild boar population on Iriomote Island in Japan.

    PubMed

    Murakami, K; Yoshikawa, S; Konishi, S; Ueno, Y; Watanabe, S; Mizoguchi, Y

    2014-08-01

    We evaluated genetic introgression from domesticated pigs into the Ryukyu wild boar (RWB) population on Iriomote Island based on their genetic structure and diversity. We used a combination of mitochondrial DNA D-loop region (596 bp) polymorphisms and 23 microsatellite markers. RWBs (n = 130) were collected from 18 locations on Iriomote Island and compared with 66 reference samples of European and Asian domestic pigs. We identified six distinct haplotypes, involving 22 single nucleotide polymorphisms (including one insertion) in the RWB population. The phylogenetic tree had two branches: the RWB group and domestic lineage. Fourteen of 130 RWBs (10.8%) belonged to the European domestic lineage, including 11 RWBs from the Panari Islands, northwest of Iriomote Main Island (IMI). The heterozygosity values, total number of alleles, number of effective alleles and polymorphism information content of the RWB groups were lower than those of the European domestic groups. The RWB population on IMI had a lower heterozygous deficiency index (FIS = 0.059) than did the other populations, which indicates that this population was more inbred. There was a large genetic distance (FST = 0.560) between RWBs on IMI and the Meishan populations. Structure analysis using the 23 microsatellite markers revealed that 16 RWBs had an admixture pattern between RWB and domesticated pig breeds. These results suggest that gene flow may have occurred from domestic pigs to RWBs and demonstrate that there was low genetic variation in the IMI population. PMID:24754898

  8. Integrative Taxonomy of Southeast Asian Snail-Eating Turtles (Geoemydidae: Malayemys) Reveals a New Species and Mitochondrial Introgression

    PubMed Central

    Ihlow, Flora; Vamberger, Melita; Flecks, Morris; Hartmann, Timo; Cota, Michael; Makchai, Sunchai; Meewattana, Pratheep; Dawson, Jeffrey E.; Kheng, Long; Rödder, Dennis; Fritz, Uwe

    2016-01-01

    Based on an integrative taxonomic approach, we examine the differentiation of Southeast Asian snail-eating turtles using information from 1863 bp of mitochondrial DNA, 12 microsatellite loci, morphology and a correlative species distribution model. Our analyses reveal three genetically distinct groups with limited mitochondrial introgression in one group. All three groups exhibit distinct nuclear gene pools and distinct morphology. Two of these groups correspond to the previously recognized species Malayemys macrocephala (Chao Phraya Basin) and M. subtrijuga (Lower Mekong Basin). The third and genetically most divergent group from the Khorat Basin represents a previously unrecognized species, which is described herein. Although Malayemys are extensively traded and used for religious release, only few studied turtles appear to be translocated by humans. Historic fluctuations in potential distributions were assessed using species distribution models (SDMs). The Last Glacial Maximum (LGM) projection of the predictive SDMs suggests two distinct glacial distribution ranges, implying that the divergence of M. macrocephala and M. subtrijuga occurred in allopatry and was triggered by Pleistocene climate fluctuations. Only the projection derived from the global circulation model MIROC reveals a distinct third glacial distribution range for the newly discovered Malayemys species. PMID:27050302

  9. Integrative Taxonomy of Southeast Asian Snail-Eating Turtles (Geoemydidae: Malayemys) Reveals a New Species and Mitochondrial Introgression.

    PubMed

    Ihlow, Flora; Vamberger, Melita; Flecks, Morris; Hartmann, Timo; Cota, Michael; Makchai, Sunchai; Meewattana, Pratheep; Dawson, Jeffrey E; Kheng, Long; Rödder, Dennis; Fritz, Uwe

    2016-01-01

    Based on an integrative taxonomic approach, we examine the differentiation of Southeast Asian snail-eating turtles using information from 1863 bp of mitochondrial DNA, 12 microsatellite loci, morphology and a correlative species distribution model. Our analyses reveal three genetically distinct groups with limited mitochondrial introgression in one group. All three groups exhibit distinct nuclear gene pools and distinct morphology. Two of these groups correspond to the previously recognized species Malayemys macrocephala (Chao Phraya Basin) and M. subtrijuga (Lower Mekong Basin). The third and genetically most divergent group from the Khorat Basin represents a previously unrecognized species, which is described herein. Although Malayemys are extensively traded and used for religious release, only few studied turtles appear to be translocated by humans. Historic fluctuations in potential distributions were assessed using species distribution models (SDMs). The Last Glacial Maximum (LGM) projection of the predictive SDMs suggests two distinct glacial distribution ranges, implying that the divergence of M. macrocephala and M. subtrijuga occurred in allopatry and was triggered by Pleistocene climate fluctuations. Only the projection derived from the global circulation model MIROC reveals a distinct third glacial distribution range for the newly discovered Malayemys species. PMID:27050302

  10. Political Alienation among Migrant Youths: Exploring the Mechanisms of Political Alienation and Acculturation among Migrant Youths in Norwegian Schools

    ERIC Educational Resources Information Center

    Solhaug, Trond

    2012-01-01

    This article addresses the following question: What characterizes the mechanisms of political alienation among non-Western immigrant students, and how might these mechanisms be related to student's acculturation attitudes? A theory of political alienation and acculturation is applied. Substantial quantitative data from Norwegian upper secondary…

  11. Multilocus phylogeography of the common lizard Zootoca vivipara at the Ibero-Pyrenean suture zone reveals lowland barriers and high-elevation introgression

    PubMed Central

    2013-01-01

    Background The geographic distribution of evolutionary lineages and the patterns of gene flow upon secondary contact provide insight into the process of divergence and speciation. We explore the evolutionary history of the common lizard Zootoca vivipara (= Lacerta vivipara) in the Iberian Peninsula and test the role of the Pyrenees and the Cantabrian Mountains in restricting gene flow and driving lineage isolation and divergence. We also assess patterns of introgression among lineages upon secondary contact, and test for the role of high-elevation trans-mountain colonisations in explaining spatial patterns of genetic diversity. We use mtDNA sequence data and genome-wide AFLP loci to reconstruct phylogenetic relationships among lineages, and measure genetic structure. Results The main genetic split in mtDNA corresponds generally to the French and Spanish sides of the Pyrenees as previously reported, in contrast to genome-wide AFLP data, which show a major division between NW Spain and the rest. Both types of markers support the existence of four distinct and geographically congruent genetic groups, which are consistent with major topographic barriers. Both datasets reveal the presence of three independent contact zones between lineages in the Pyrenean region, one in the Basque lowlands, one in the low-elevation mountains of the western Pyrenees, and one in the French side of the central Pyrenees. The latter shows genetic evidence of a recent, high-altitude trans-Pyrenean incursion from Spain into France. Conclusions The distribution and age of major lineages is consistent with a Pleistocene origin and a role for both the Pyrenees and the Cantabrian Mountains in driving isolation and differentiation of Z. vivipara lineages at large geographic scales. However, mountain ranges are not always effective barriers to dispersal, and have not prevented a recent high-elevation trans-Pyrenean incursion that has led to asymmetrical introgression among divergent lineages

  12. Development of a genetic sexing strain in Bactrocera carambolae (Diptera: Tephritidae) by introgression of sex sorting components from B. dorsalis, Salaya1 strain

    PubMed Central

    2014-01-01

    Background The carambola fruit fly, Bactrocera carambolae Drew & Hancock is a high profile key pest that is widely distributed in the southwestern ASEAN region. In addition, it has trans-continentally invaded Suriname, where it has been expanding east and southward since 1975. This fruit fly belongs to Bactrocera dorsalis species complex. The development and application of a genetic sexing strain (Salaya1) of B. dorsalis sensu stricto (s.s.) (Hendel) for the sterile insect technique (SIT) has improved the fruit fly control. However, matings between B. dorsalis s.s. and B. carambolae are incompatible, which hinder the application of the Salaya1 strain to control the carambola fruit fly. To solve this problem, we introduced genetic sexing components from the Salaya1 strain into the B. carambolae genome by interspecific hybridization. Results Morphological characteristics, mating competitiveness, male pheromone profiles, and genetic relationships revealed consistencies that helped to distinguish Salaya1 and B. carambolae strains. A Y-autosome translocation linking the dominant wild-type allele of white pupae gene and a free autosome carrying a recessive white pupae homologue from the Salaya1 strain were introgressed into the gene pool of B. carambolae. A panel of Y-pseudo-linked microsatellite loci of the Salaya1 strain served as markers for the introgression experiments. This resulted in a newly derived genetic sexing strain called Salaya5, with morphological characteristics corresponding to B. carambolae. The rectal gland pheromone profile of Salaya5 males also contained a distinctive component of B. carambolae. Microsatellite DNA analyses confirmed the close genetic relationships between the Salaya5 strain and wild B. carambolae populations. Further experiments showed that the sterile males of Salaya5 can compete with wild males for mating with wild females in field cage conditions. Conclusions Introgression of sex sorting components from the Salaya1 strain to a

  13. Analysis of the mesotelencephalic dopamine system by quantitative-trait locus introgression.

    PubMed

    Vadasz, C; Sziraki, I; Sasvari, M; Kabai, P; Murthy, L R; Saito, M; Laszlovszky, I

    1998-11-01

    One of the significant factors that affect brain dopamine function is the activity of tyrosine hydroxylase (TH), the first and rate-limiting enzyme in catecholamine biosynthesis. For the analysis of the genetically determined role of dopamine function and TH in behavior and in the regulatory mechanisms of the mesotelencephalic dopamine system we devised a novel genetic strategy (Vadasz; Mouse Genome 88:16-18; 1990). We hypothesized that phenotypic introgression and recombinant fixation could ensure the transfer of Quantitative Trait Loci (QTL) from one strain onto the genetic background of another strain, and new, genetically very similar quasi-congenic strains could be created that would carry individual QTLs, or QTLs in various combinations. Here we summarize the construction of the first set of QTL Introgression strains, and present evidence that QTLs that are responsible for the continuous variation of mesencephalic tyrosine hydroxylase activity (TH/MES), have been transferred onto the C57BL/6By (B6) strain background from BALB/cJ (C) and CXBI (I) donor strains with high and low TH/MES, respectively. The QTL transfer was carried out in two directions by repeated backcross-intercross cycles with concomitant selection for the extreme high and low expressions of TH/MES in replicates, resulting in four QTL Introgression lines. Analysis of regional brain TH activities in the course of the QTL introgression indicated that (a) TH activity in B6.I lines showed quite limited heritability, (b) TH/MES was not highly correlated with striatal TH, and (c) the control of hypothalamic and olfactory tubercle TH activities was largely independent from that of TH/MES. Examination of the open-field (OF) behavior data demonstrated that TH activity did not correlate significantly with OF behavior. After 5 backcross-intercross cycles, TH/MES in each replicate line was still significantly different from that of the B6 background strain. A genomewide scanning of microsatellite markers

  14. Evidence for the introduction of the Asian red alga Neosiphonia japonica and its introgression with Neosiphonia harveyi (Ceramiales, Rhodophyta) in the Northwest Atlantic.

    PubMed

    Savoie, Amanda M; Saunders, Gary W

    2015-12-01

    There is currently conflict in the literature on the taxonomic status of the reportedly cosmopolitan species Neosiphonia harveyi, a common red alga along the coast of Atlantic Canada and New England, USA. Neosiphonia harveyi sensu lato was assessed using three molecular markers: COI-5P, ITS and rbcL. All three markers clearly delimited three genetic species groups within N. harveyi sensu lato in this region, which we identified as N. harveyi, N. japonica and Polysiphonia akkeshiensis (here resurrected from synonymy with N. japonica). Although Neosiphonia harveyi is considered by some authors to be introduced to the Atlantic from the western Pacific, it was only confirmed from the North Atlantic suggesting it is native to this area. In contrast, Neosiphonia japonica was collected from only two sites in Rhode Island, USA, as well as from its reported native range in Asia (South Korea), which when combined with data in GenBank indicates that this species was introduced to the Northwest Atlantic. The GenBank data further indicate that N. japonica was also introduced to North Carolina, Spain, Australia and New Zealand. Despite the fact that all three markers clearly delimited N. harveyi and N. japonica as distinct genetic species groups, the ITS sequences for some N. harveyi individuals displayed mixed patterns and additivity indicating introgression of nuclear DNA from N. japonica into N. harveyi in the Northwest Atlantic. Introgression of DNA from an introduced species to a native species (i.e. 'genetic pollution') is one of the possible consequences of species introductions, and we believe this is the first documented evidence for this phenomenon in red algae. PMID:26477438

  15. Cucumis monosomic alien addition lines: morphological, cytological, and genotypic analyses.

    PubMed

    Chen, Jin-Feng; Luo, Xiang-Dong; Qian, Chun-Tao; Jahn, Molly M; Staub, Jack E; Zhuang, Fei-Yun; Lou, Qun-Feng; Ren, Gang

    2004-05-01

    Cucumis hystrix Chakr. (HH, 2n=24), a wild relative of the cultivated cucumber, possesses several potentially valuable disease-resistance and abiotic stress-tolerance traits for cucumber ( C. sativus L., CC, 2n=14) improvement. Numerous attempts have been made to transfer desirable traits since the successful interspecific hybridization between C. hystrix and C. sativus, one of which resulted in the production of an allotriploid (HCC, 2n=26: one genome of C. hystrix and two of C. sativus). When this genotype was treated with colchicine to induce polyploidy, two monosomic alien addition lines (MAALs) (plant nos. 87 and 517: 14 CC+1 H, 2n=15) were recovered among 252 viable plants. Each of these plants was morphologically distinct from allotriploids and cultivated cucumbers. Cytogenetic and molecular marker analyses were performed to confirm the genetic constitution and further characterize these two MAALs. Chromosome counts made from at least 30 meristematic cells from each plant confirmed 15 nuclear chromosomes. In pollen mother cells of plant nos. 87 and 517, seven bivalents and one univalent were observed at diakinesis and metaphase I; the frequency of trivalent formation was low (about 4-5%). At anaphase I and II, stochastic and asymmetric division led to the formation of two gamete classes: n=7 and n=8; however, pollen fertility was relatively high. Pollen stainability in plant no. 87 was 86.7% and in plant no. 517 was 93.2%. Random amplified polymorphic DNA analysis was performed using 100 random 10-base primers. Genotypes obtained with eight primers (A-9, A-11, AH-13, AI-19, AJ-18, AJ-20, E-19, and N-20) showed a band common to the two MAAL plants and C. hystrix that was absent in C. sativus, confirming that the alien chromosomes present in the MAALs were derived from C. hystrix. Morphological differences and differences in banding patterns were also observed between plant nos. 87 and 517 after amplification with primers AI-5, AJ-13, N-12, and N-20

  16. 8 CFR 244.5 - Temporary treatment benefits for eligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Temporary treatment benefits for eligible aliens. 244.5 Section 244.5 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION... for eligible aliens. (a) Prior to the registration period. Prior to the registration...

  17. 8 CFR 244.5 - Temporary treatment benefits for eligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Temporary treatment benefits for eligible aliens. 244.5 Section 244.5 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION... for eligible aliens. (a) Prior to the registration period. Prior to the registration...

  18. 22 CFR 40.203 - Alien entitled to A, E, or G nonimmigrant classification.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Alien entitled to A, E, or G nonimmigrant... § 40.203 Alien entitled to A, E, or G nonimmigrant classification. An alien entitled to nonimmigrant... to receive an immigrant visa until the alien executes a written waiver of all rights,...

  19. 26 CFR 1.871-5 - Loss of residence by an alien.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Loss of residence by an alien. 1.871-5 Section 1... (CONTINUED) INCOME TAXES Nonresident Aliens and Foreign Corporations § 1.871-5 Loss of residence by an alien. An alien who has acquired residence in the United States retains his status as a resident until...

  20. 8 CFR 209.2 - Adjustment of status of alien granted asylum.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) Inadmissible alien. An applicant who is not admissible to the United States as described in 8 CFR 209.2(a)(1)(v... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Adjustment of status of alien granted asylum. 209.2 Section 209.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY...