72 research outputs found

    Petrolio e politica nella decolonizzazione Algerina: verso un network energetico Europeo?

    Get PDF
    Le relazioni tra Francia e Italia nella guerra d’Algeria sono state oggetto di diverse analisi storiche; questo lavoro si concentra sul ruolo dell’industria petrolifera nelle relazioni tra i due paesi nel periodo specifico. Le riserve d’idrocarburi algerine furono scoperte nel 1956, due anni dopo l’inizio della guerra. I ritrovamenti ebbero una notevole eco in Francia, e la possibilità di diventare un paese produttore di petrolio rese più urgente il dibattito sull’amministrazione del Sahara e sull’opportunità di aprire le porte alle compagnie straniere. Questa ricerca ha come obiettivo l’esame delle azioni intraprese dalla Francia per la messa a punto di un’industria petrolifera nel Sahara, e le parallele strategie dell’industria petrolifera internazionale per la penetrazione in un nuovo territorio e in un’area contestata. In particolare, l’analisi si concentra sulla strategia dell’Eni, la compagnia di Stato Italiana, che rifiutò apertamente di collaborare con il governo francese per mantenere un atteggiamento pro-arabo. L’articolo punta a ricostruire il dibattito sulle risorse del sottosuolo sahariano, il problema del controllo del territorio e le frizioni tra l’industria petrolifera di Stato europea e le grandi multinazionali americane, nel contesto più ampio della decolonizzazione, dei negoziati per la costruzione dell’Unione Europea e della ricerca di una maggiore indipendenza dagli Stati Uniti. Italian-French relations during the Algerian war have been the subject of thorough historical investigations; this paper concentrates on the hydrocarbon industry and its role in the Algerian decolonization process and in the Italian-French relations. Algerian hydrocarbon reserves were found in 1956, two years after the outbreak of the war. The discovery had a considerable impact in France, where the possibility of becoming an oil exporting country reinvigorated the debate over the management of the Saharan area and on whether (and to which degree) to allow the presence of foreign oil companies in its exploitation. The research aims to investigate the actions taken by the French government for the set-up of an oil industry in the Sahara and the parallel strategies of the international oil industry for the penetration of a new territory in a contented area. In particular, the paper focuses on the Italian State company ENI, which openly refused to collaborate with the French government in order to maintain a pro-Arab approach. This paper aims to reconstruct the debate over the Saharan oil resources, the control over the territory and the frictions between European SOEs and the American oil giants, in the broader contest of decolonization, the negotiations for the construction of the European Union and the research for more independence from the United States

    A large genome-wide association study of age-related macular degeneration highlights contributions of rare and common variants

    Get PDF
    Advanced age-related macular degeneration (AMD) is the leading cause of blindness in the elderly with limited therapeutic options. Here, we report on a study of \u3e12 million variants including 163,714 directly genotyped, most rare, protein-altering variant. Analyzing 16,144 patients and 17,832 controls, we identify 52 independently associated common and rare variants (P \u3c 5×10–8) distributed across 34 loci. While wet and dry AMD subtypes exhibit predominantly shared genetics, we identify the first signal specific to wet AMD, near MMP9 (difference-P = 4.1×10–10). Very rare coding variants (frequency \u3c 0.1%) in CFH, CFI, and TIMP3 suggest causal roles for these genes, as does a splice variant in SLC16A8. Our results support the hypothesis that rare coding variants can pinpoint causal genes within known genetic loci and illustrate that applying the approach systematically to detect new loci requires extremely large sample sizes

    Glycomics meets lipidomics - associations of N-glycans with classical lipids, glycerophospholipids, and sphingolipids in three European populations

    Get PDF
    Recently, high-throughput technologies have been made available which allow the measurement of a broad spectrum of glycomics and lipidomics parameters in many samples. The aim of this study was to apply these methods and investigate associations between 46 glycan and 183 lipid traits measured in blood of 2041 Europeans from three different local populations (Croatia - VIS cohort; Sweden - NSPHS cohort; Great Britain - ORCADES cohort). N-glycans have been analyzed with High Performance Liquid Chromatography (HPLC) and lipids with Electrospray Ionization Tandem Mass Spectrometry (ESI-MS/MS) covering sterol lipids, glycerolipids, glycerophospholipids and sphingolipids in eight subclasses. Overall, 8418 associations were calculated using linear mixed effect models adjusted for pedigree, sex, age and multiple testing. We found 330 significant correlations in VIS. Pearson's correlation coefficient r ranged from −0.27 to 0.34 with corresponding p-values between 1.45 × 10−19 and 4.83 × 10−6, indicating statistical significance. A total of 71 correlations in VIS could be replicated in NSPHS (r = [−0.19; 0.35], p = [4.16 × 10−18; 9.38 × 10−5]) and 31 correlations in VIS were also found in ORCADES (r = [−0.20; 0.24], p = [2.69 × 10−10; 7.55 × 10−5]). However, in total only 10 correlations between a subset of triantennary glycans and unsaturated phosphatidylcholine, saturated ceramide, and sphingomyelin lipids in VIS (r = [0.18; 0.34], p = [2.98 × 10−21; 1.69 × 10−06]) could be replicated in both NSPHS and ORCADES. In summary, the results show strong and consistent associations between certain glycans and lipids in all populations, but also population-specific correlations which may be caused by environmental and genetic differences. These associations point towards potential interactive metabolic pathways

    Genetic Determinants of Circulating Sphingolipid Concentrations in European Populations

    Get PDF
    Sphingolipids have essential roles as structural components of cell membranes and in cell signalling, and disruption of their metabolism causes several diseases, with diverse neurological, psychiatric, and metabolic consequences. Increasingly, variants within a few of the genes that encode enzymes involved in sphingolipid metabolism are being associated with complex disease phenotypes. Direct experimental evidence supports a role of specific sphingolipid species in several common complex chronic disease processes including atherosclerotic plaque formation, myocardial infarction (MI), cardiomyopathy, pancreatic beta-cell failure, insulin resistance, and type 2 diabetes mellitus. Therefore, sphingolipids represent novel and important intermediate phenotypes for genetic analysis, yet little is known about the major genetic variants that influence their circulating levels in the general population. We performed a genome-wide association study (GWAS) between 318,237 single-nucleotide polymorphisms (SNPs) and levels of circulating sphingomyelin (SM), dihydrosphingomyelin (Dih-SM), ceramide (Cer), and glucosylceramide (GluCer) single lipid species (33 traits); and 43 matched metabolite ratios measured in 4,400 subjects from five diverse European populations. Associated variants (32) in five genomic regions were identified with genome-wide significant corrected p-values ranging down to 9.08 x 10(-66). The strongest associations were observed in or near 7 genes functionally involved in ceramide biosynthesis and trafficking: SPTLC3, LASS4, SGPP1, ATP10D, and FADS1-3. Variants in 3 loci (ATP10D, FADS3, and SPTLC3) associate with MI in a series of three German MI studies. An additional 70 variants across 23 candidate genes involved in sphingolipid-metabolizing pathways also demonstrate association (p = 10(-4) or less). Circulating concentrations of several key components in sphingolipid metabolism are thus under strong genetic control, and variants in these loci can be tested for a role in the development of common cardiovascular, metabolic, neurological, and psychiatric diseases

    Effect of HLA-DRB1 alleles and genetic variants on the development of neutralizing antibodies to interferon beta in the BEYOND and BENEFIT trials

    Get PDF
    BACKGROUND: Treatment of multiple sclerosis (MS) with interferon β can lead to the development of antibodies directed against interferon β that interfere with treatment efficacy. Several observational studies have proposed different HLA alleles and genetic variants associated with the development of antibodies against interferon β. OBJECTIVE: To validate the proposed genetic markers and to identify new markers. METHODS: Associations of genetic candidate markers with antibody presence and development were examined in a post hoc analysis in 941 patients treated with interferon β-1b in the Betaferon® Efficacy Yielding Outcomes of a New Dose (BEYOND) and BEtaseron®/BEtaferon® in Newly Emerging multiple sclerosis For Initial Treatment (BENEFIT) prospective phase III trials. All patients were treated with interferon β-1b for at least 6 months. In addition, a genome-wide association study was conducted to identify new genetic variants. RESULTS: We confirmed an increased risk for carriers of HLA-DRB1*04:01 (odds ratio (OR) = 3.3, p = 6.9 × 10-4) and HLA-DRB1*07:01 (OR = 1.8, p = 3.5 × 10-3) for developing neutralizing antibodies (NAbs). Several additional, previously proposed HLA alleles and genetic variants showed nominally significant associations. In the exploratory analysis, variants in the HLA region were associated with NAb development at genome-wide significance (OR = 2.6, p = 2.30 × 10-15). CONCLUSION: The contribution of HLA alleles and HLA-associated single-nucleotide polymorphisms (SNPs) to the development and titer of antibodies against interferon β was confirmed in the combined analysis of two multi-national, multi-center studies

    Modeling of Environmental Effects in Genome-Wide Association Studies Identifies SLC2A2 and HP as Novel Loci Influencing Serum Cholesterol Levels

    Get PDF
    Genome-wide association studies (GWAS) have identified 38 larger genetic regions affecting classical blood lipid levels without adjusting for important environmental influences. We modeled diet and physical activity in a GWAS in order to identify novel loci affecting total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride levels. The Swedish (SE) EUROSPAN cohort (NSE = 656) was screened for candidate genes and the non-Swedish (NS) EUROSPAN cohorts (NNS = 3,282) were used for replication. In total, 3 SNPs were associated in the Swedish sample and were replicated in the non-Swedish cohorts. While SNP rs1532624 was a replication of the previously published association between CETP and HDL cholesterol, the other two were novel findings. For the latter SNPs, the p-value for association was substantially improved by inclusion of environmental covariates: SNP rs5400 (pSE,unadjusted = 3.6×10−5, pSE,adjusted = 2.2×10−6, pNS,unadjusted = 0.047) in the SLC2A2 (Glucose transporter type 2) and rs2000999 (pSE,unadjusted = 1.1×10−3, pSE,adjusted = 3.8×10−4, pNS,unadjusted = 0.035) in the HP gene (Haptoglobin-related protein precursor). Both showed evidence of association with total cholesterol. These results demonstrate that inclusion of important environmental factors in the analysis model can reveal new genetic susceptibility loci

    Hundreds of variants clustered in genomic loci and biological pathways affect human height

    Get PDF
    Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.

    Genome-wide association study identifies novel loci associated with circulating phospho- and sphingolipid concentrations.

    Get PDF
    Phospho- and sphingolipids are crucial cellular and intracellular compounds. These lipids are required for active transport, a number of enzymatic processes, membrane formation, and cell signalling. Disruption of their metabolism leads to several diseases, with diverse neurological, psychiatric, and metabolic consequences. A large number of phospholipid and sphingolipid species can be detected and measured in human plasma. We conducted a meta-analysis of five European family-based genome-wide association studies (N = 4034) on plasma levels of 24 sphingomyelins (SPM), 9 ceramides (CER), 57 phosphatidylcholines (PC), 20 lysophosphatidylcholines (LPC), 27 phosphatidylethanolamines (PE), and 16 PE-based plasmalogens (PLPE), as well as their proportions in each major class. This effort yielded 25 genome-wide significant loci for phospholipids (smallest P-value = 9.88×10(-204)) and 10 loci for sphingolipids (smallest P-value = 3.10×10(-57)). After a correction for multiple comparisons (P-value<2.2×10(-9)), we observed four novel loci significantly associated with phospholipids (PAQR9, AGPAT1, PKD2L1, PDXDC1) and two with sphingolipids (PLD2 and APOE) explaining up to 3.1% of the variance. Further analysis of the top findings with respect to within class molar proportions uncovered three additional loci for phospholipids (PNLIPRP2, PCDH20, and ABDH3) suggesting their involvement in either fatty acid elongation/saturation processes or fatty acid specific turnover mechanisms. Among those, 14 loci (KCNH7, AGPAT1, PNLIPRP2, SYT9, FADS1-2-3, DLG2, APOA1, ELOVL2, CDK17, LIPC, PDXDC1, PLD2, LASS4, and APOE) mapped into the glycerophospholipid and 12 loci (ILKAP, ITGA9, AGPAT1, FADS1-2-3, APOA1, PCDH20, LIPC, PDXDC1, SGPP1, APOE, LASS4, and PLD2) to the sphingolipid pathways. In large meta-analyses, associations between FADS1-2-3 and carotid intima media thickness, AGPAT1 and type 2 diabetes, and APOA1 and coronary artery disease were observed. In conclusion, our study identified nine novel phospho- and sphingolipid loci, substantially increasing our knowledge of the genetic basis for these traits

    Automated workflow-based exploitation of pathway databases provides new insights into genetic associations of metabolite profiles

    Get PDF
    Background: Genome-wide association studies (GWAS) have identified many common single nucleotide polymorphisms (SNPs) that associate with clinical phenotypes, but these SNPs usually explain just a small part of the heritability and have relatively modest effect sizes. In contrast, SNPs that associate with metabolite levels generally explain a higher percentage of the genetic variation and demonstrate larger effect sizes. Still, the discovery of SNPs associated with metabolite levels is challenging since testing all metabolites measured in typical metabolomics studies with all SNPs comes with a severe multiple testing penalty. We have developed an automated workflow approach that utilizes prior knowledge of biochemical pathways present in databases like KEGG and BioCyc to generate a smaller SNP set relevant to the metabolite. This paper explores the opportunities and challenges in the analysis of GWAS of metabolomic phenotypes and provides novel insights into the genetic basis of metabolic variation through the re-analysis of published GWAS datasets. Results: Re-analysis of the published GWAS dataset from Illig et al. (Nature Genetics, 2010) using a pathway-based workflow (http://www.myexperiment.org/packs/319.html), confirmed previously identified hits and identified a new locus of human metabolic individuality, associating Aldehyde dehydrogenase family1 L1 (ALDH1L1) with serine/glycine ratios in blood. Replication in an independent GWAS dataset of phospholipids (Demirkan et al., PLoS Genetics, 2012) identified two novel loci supported by additional literature evidence: GPAM (Glycerol-3 phosphate acyltransferase) and CBS (Cystathionine beta-synthase). In addition, the workflow approach provided novel insight into the affected pathways and relevance of some of these gene-metabolite pairs in disease development and progression. Conclusions: We demonstrate the utility of automated exploitation of background knowledge present in pathway databases for the analysis of GWAS datasets of metabolomic phenotypes. We report novel loci and potential biochemical mechanisms that contribute to our understanding of the genetic basis of metabolic variation and its relationship to disease development and progression
    corecore