Contributions of common genetic variants to risk of schizophrenia among individuals of African and Latino ancestry

Schizophrenia is a common, chronic and debilitating neuropsychiatric syndrome affecting tens of millions of individuals worldwide. While rare genetic variants play a role in the etiology of schizophrenia, most of the currently explained liability is within common variation, suggesting that variation predating the human diaspora out of Africa harbors a large fraction of the common variant attributable heritability. However, common variant association studies in schizophrenia have concentrated mainly on cohorts of European descent. We describe genome-wide association studies of 6152 cases and 3918 controls of admixed African ancestry, and of 1234 cases and 3090 controls of Latino ancestry, representing the largest such study in these populations to date. Combining results from the samples with African ancestry with summary statistics from the Psychiatric Genomics Consortium (PGC) study of schizophrenia yielded seven newly genome-wide significant loci, and we identified an additional eight loci by incorporating the results from samples with Latino ancestry. Leveraging population differences in patterns of linkage disequilibrium, we achieve improved fine-mapping resolution at 22 previously reported and 4 newly significant loci. Polygenic risk score profiling revealed improved prediction based on trans-ancestry meta-analysis results for admixed African (Nagelkerke’s R2 = 0.032; liability R2 = 0.017; P < 10−52), Latino (Nagelkerke’s R2 = 0.089; liability R2 = 0.021; P < 10−58), and European individuals (Nagelkerke’s R2 = 0.089; liability R2 = 0.037; P < 10−113), further highlighting the advantages of incorporating data from diverse human populations

Age at first birth in women is genetically associated with increased risk of schizophrenia

Prof. Paunio on PGC:n jäsenPrevious studies have shown an increased risk for mental health problems in children born to both younger and older parents compared to children of average-aged parents. We previously used a novel design to reveal a latent mechanism of genetic association between schizophrenia and age at first birth in women (AFB). Here, we use independent data from the UK Biobank (N = 38,892) to replicate the finding of an association between predicted genetic risk of schizophrenia and AFB in women, and to estimate the genetic correlation between schizophrenia and AFB in women stratified into younger and older groups. We find evidence for an association between predicted genetic risk of schizophrenia and AFB in women (P-value = 1.12E-05), and we show genetic heterogeneity between younger and older AFB groups (P-value = 3.45E-03). The genetic correlation between schizophrenia and AFB in the younger AFB group is -0.16 (SE = 0.04) while that between schizophrenia and AFB in the older AFB group is 0.14 (SE = 0.08). Our results suggest that early, and perhaps also late, age at first birth in women is associated with increased genetic risk for schizophrenia in the UK Biobank sample. These findings contribute new insights into factors contributing to the complex bio-social risk architecture underpinning the association between parental age and offspring mental health.Peer reviewe

Search for H→γγ produced in association with top quarks and constraints on the Yukawa coupling between the top quark and the Higgs boson using data taken at 7 TeV and 8 TeV with the ATLAS detector

A search is performed for Higgs bosons produced in association with top quarks using the diphoton decay mode of the Higgs boson. Selection requirements are optimized separately for leptonic and fully hadronic final states from the top quark decays. The dataset used corresponds to an integrated luminosity of 4.5 fb−14.5 fb−1 of proton–proton collisions at a center-of-mass energy of 7 TeV and 20.3 fb−1 at 8 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No significant excess over the background prediction is observed and upper limits are set on the tt¯H production cross section. The observed exclusion upper limit at 95% confidence level is 6.7 times the predicted Standard Model cross section value. In addition, limits are set on the strength of the Yukawa coupling between the top quark and the Higgs boson, taking into account the dependence of the tt¯H and tH cross sections as well as the H→γγ branching fraction on the Yukawa coupling. Lower and upper limits at 95% confidence level are set at −1.3 and +8.0 times the Yukawa coupling strength in the Standard Model

Swine infection by Streptococcus suis: a retrospective study Infecção em suínos por Streptococcus suis: estudo retrospectivo

The epidemic aspects of swine infections caused by Streptococcus suis were studied, focusing mainly on the occurrence of several serotypes. A total of 323 samples of S. suis were isolated from clinically ill animals, serotyped according to the co-agglutination procedure, and analyzed. The serotyping revealed that S. suis was present in several Brazilian states. The largest number was isolated from the states of Minas Gerais (62.5%), São Paulo (10.8%), and Paraná (9.3%). Serotype 2 was the most frequent (61.0%), followed by the serotypes 1, 3, 4, 7, and 8. The largest number of isolations was obtained from the brain (60.1%), followed by the lungs (10.4%). About 9.4% of the cases were due to septicemia.<br>Estudaram-se os aspectos epidêmicos das infecções de suínos causadas por Streptococcus suis, enfocando, principalmente, a ocorrência de diferentes sorotipos. Foram analisadas 323 amostras isoladas de animais clinicamente doentes, as quais foram sorotipadas de acordo com o procedimento de co-aglutinação. Foi verificado que S. suis está presente em vários estados brasileiros e o maior número de isolados originou-se dos estados de Minas Gerais (62,5%), São Paulo (10,8%) e Paraná (9,3%). O sorotipo 2 foi o mais freqüente (61.0%), seguido pelos sorotipos 1, 3, 4, 7 e 8. Os isolamentos foram obtidos principalmente de cérebro (60,1%) e pulmões (10,4%). Os casos de septicemia representaram 9,4%

Medley spectrometer for light ions in neutron-induced reactions at 175 MeV

We have upgraded the Medley spectrometer to measure neutron-induced double differential cross-sections for light-ion production, with neutron energies up to 175 MeV. Measurements were performed at the quasi-monoenergetic neutron beam line at the The Svedberg Laboratory, in Uppsala (Sweden). Medley is a spectrometer system composed of eight three-element telescope detectors; ΔE-E technique is used for particle identification and total kinetic energy measurement. We have improved particle separation and installed new detectors that fully stop ions with kinetic energy up to 170 MeV. To reduce the contribution of the low energy tail in the quasi-monoenergetic neutron spectrum, we have applied time-of-flight techniques and investigated the results for measurements with 175 MeV neutrons. We have investigated the response function of the CsI(Tl) scintillators and describe a method for efficiency correction. We have studied the signal-to-background ratio of the new configuration of the spectrometer and of the collimation system. A method to obtain absolute cross-section normalization, separating the peak neutrons from the low-energy tail, is proposed. Finally we have characterized the 175 MeV quasi-monoenergetic neutron spectrum with the Medley spectrometer. This upgraded configuration has been used in 2007 and 2009 for light-ion production measurements at 175 MeV from C, Si, O, Fe, Bi and U