3,052 research outputs found

    The use of measured genotype information in the analysis of quantitative phenotypes in man.

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    We have begun a measured genotype approach to the genetic analysis of lipid and lipoprotein variability. This approach enables one to simultaneously estimate the frequencies and effects of alleles at specific loci along with the residual polygenetic variance component. In this study we consider the contribution of three common alleles at the locus coding for apolipoprotein E to interindividual variation of total cholesterol, betalipoprotein, and triglyceride levels. A sample of 102 nuclear families consisting of 434 individuals was studied. The frequencies of the 蔚2, 蔚3, and 蔚4 alleles in this sample are 0路137,0路740, and 0路123, respectively. In separate analyses of cholesterol and betalipoprotein levels, a complete model that includes the effects of the six apo E genotypes, unmeasured polygenes, and individual specific environmental effects fits these data significantly better than a reduced model that does not include the effects of the apo E polymorphism or a reduced model that does not include the effects of polygenes. On the average the 蔚2 allele lowers total cholesterol and betalipoprotein levels by 0路425 mmol/l and 0路811 units, respectively. The 蔚4 allele is associated with an average increase of these phenotypes by 0路255 mmol/l and 0路628 units, respectively. Simultaneous estimates of the interindividual variability of total cholesterol levels attributable to the apo E polymorphism and to residual polygenic effects are 8% and 56%, respectively. For betalipoprotein levels, we simultaneously estimate these values to be 7% and 42%, respectively. A reduced model including the effects of polygenes but not the effects of the apo E polymorphism fitted the triglyceride data as well as the complete model. The estimate of the fraction of interindividual variability associated with polygenetic effects was 26.5%. We review our present understanding of the genetic architecture underlying variability of cholesterol levels in the population at large and infer that the majority of the genetic variability may be accounted for by polymorphic gene loci with moderate effects on cholesterol levels.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65212/1/j.1469-1809.1987.tb00874.x.pd

    Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s鈭=8 TeV with ATLAS

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    Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s鈭=8 TeV. The analysis is performed in the H 鈫 纬纬 decay channel using 20.3 fb鈭1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp 鈫 H 鈫 纬纬 fiducial cross section is measured to be 43.2 卤9.4(stat.) 鈭掆2.9 +鈥3.2 (syst.) 卤1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations

    Measurement of the production of a W boson in association with a charm quark in pp collisions at 鈭歴 = 7 TeV with the ATLAS detector