Phylogenomics of the olive tree (Olea europaea) reveals the relative contribution of ancient allo- and autopolyploidization events

Background: Polyploidization is one of the major evolutionary processes that shape eukaryotic genomes, being particularly common in plants. Polyploids can arise through direct genome doubling within a species (autopolyploidization) or through the merging of genomes from distinct species after hybridization (allopolyploidization). The relative contribution of both mechanisms in plant evolution is debated. Here we used phylogenomics to dissect the tempo and mode of duplications in the genome of the olive tree (Olea europaea), one of the first domesticated Mediterranean fruit trees. Results: Our results depict a complex scenario involving at least three past polyploidization events, of which two—at the bases of the family Oleaceae and the tribe Oleeae, respectively—are likely to be the result of ancient allopolyploidization. A more recent polyploidization involves specifically the olive tree and relatives. Conclusion: Our results show the power of phylogenomics to distinguish between allo- and auto polyploidization events and clarify the contributions of duplications in the evolutionary history of the olive tree.TG’s group acknowledges support from the Spanish Ministry of Economy and Competitiveness through grants “Centro de Excelencia Severo Ochoa 2013-2017” SEV-2012-0208 and BFU2015-67107, cofounded by the European Regional Development Fund; from the Catalan Research Agency (AGAUR) SGR857, from the CERCA programme/ Generalitat de Catalunya; and from the European Union’s Horizon 2020 research and innovation program under Marie Sklodowska-Curie grant agreement H2020-MSCA-ITN-2014-642095 and European Research Council grant agreement ERC-2016-CoG-724173. TG and PV acknowledge support from Banco Santander for the olive genome sequencing project. IJ was supported in part by a grant from the Peruvian Ministry of Education, “Beca Presidente de la República” (2013-III)

Genetic transmission of Solanum demissum (2n = 6x = 72) chromosomes from a pentaploid hybrid of S. tuberosum (2n = 4x = 48) into the aneuploid BC1 progeny

Solanum demissum is a homozygous, hexaploid wild species (2n = 6x = 72, AADDD(d)D(d)) that has long been used as a source of late blight resistance by repeated backcrossing with S. tuberosum (2n = 4x = 48, AAA(t)A(t)). To understand how S. demissum germplasm is incorporated to S. tuberosum through backcrosses, a linkage analysis of 590 DNA markers from S. demissum-specific simplex alleles was performed in an aneuploid population of 87 BC1 plants. Five hundred eighty-one markers were mapped to 38 linkage groups, of which 37 were assigned to potato chromosomes using markers of known location. Three homoeologous chromosomes were distinguished for each of the 12 potato chromosomes. Approximately 50 % of the markers were transmitted to the BC1 progeny except for chromosomes 2c, 3b and 6c, which were significantly under-represented. Two of the three homeologous chromosomes in at least nine of the chromosomes were transmitted to the BC1 progeny with negative correlations, which demonstrated that the two homeologous chromosomes paired at meiosis in the F-1 parent then separated into different gametes. Therefore, we suggest that the two negatively correlated chromosomes were the slightly differentiated genomes cytologically designated D and D-d genomes, while the remaining one was the one cytologically designated A genome of S. demissum. The S. demissum genome map will be useful in analyzing intra-locus interaction of qualitative and quantitative traits among homoeologous chromosomes and analyzing allelic variation of homeolog expression

Mortality after surgery in Europe: a 7 day cohort study

SummaryBackgroundClinical outcomes after major surgery are poorly described at the national level. Evidence of heterogeneity between hospitals and health-care systems suggests potential to improve care for patients but this potential remains unconfirmed. The European Surgical Outcomes Study was an international study designed to assess outcomes after non-cardiac surgery in Europe.MethodsWe did this 7 day cohort study between April 4 and April 11, 2011. We collected data describing consecutive patients aged 16 years and older undergoing inpatient non-cardiac surgery in 498 hospitals across 28 European nations. Patients were followed up for a maximum of 60 days. The primary endpoint was in-hospital mortality. Secondary outcome measures were duration of hospital stay and admission to critical care. We used χ2 and Fisher's exact tests to compare categorical variables and the t test or the Mann-Whitney U test to compare continuous variables. Significance was set at p<0·05. We constructed multilevel logistic regression models to adjust for the differences in mortality rates between countries.FindingsWe included 46 539 patients, of whom 1855 (4%) died before hospital discharge. 3599 (8%) patients were admitted to critical care after surgery with a median length of stay of 1·2 days (IQR 0·9–3·6). 1358 (73%) patients who died were not admitted to critical care at any stage after surgery. Crude mortality rates varied widely between countries (from 1·2% [95% CI 0·0–3·0] for Iceland to 21·5% [16·9–26·2] for Latvia). After adjustment for confounding variables, important differences remained between countries when compared with the UK, the country with the largest dataset (OR range from 0·44 [95% CI 0·19–1·05; p=0·06] for Finland to 6·92 [2·37–20·27; p=0·0004] for Poland).InterpretationThe mortality rate for patients undergoing inpatient non-cardiac surgery was higher than anticipated. Variations in mortality between countries suggest the need for national and international strategies to improve care for this group of patients.FundingEuropean Society of Intensive Care Medicine, European Society of Anaesthesiology