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Genetic correlations between quantitative traits measured in many breeding programs are pervasive. These correlations indicate that measurements of one trait carry information on other traits. Current single-trait (univariate) genomic selection does not take advantage of this information. Multivariate genomic selection on multiple traits could accomplish this but has been little explored and tested in practical breeding programs. In this study, three multivariate linear models (i.e., GBLUP, BayesA, and BayesCπ) were presented and compared to univariate models using simulated and real quantitative traits controlled by different genetic architectures. We also extended BayesA with fixed hyperparameters to a full hierarchical model that estimated hyperparameters and BayesCπ to impute missing phenotypes. We found that optimal marker-effect variance priors depended on the genetic architecture of the trait so that estimating them was beneficial. We showed that the prediction accuracy for a low-heritability trait could be significantly increased by multivariate genomic selection when a correlated high-heritability trait was available. Further, multiple-trait genomic selection had higher prediction accuracy than single-trait genomic selection when phenotypes are not available on all individuals and traits. Additional factors affecting the performance of multiple-trait genomic selection were explored. 相似文献
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Thierry Jauniaux Mutien-Marie Garigliany Pauline Loos Jean-Luc Bourgain Thibaut Bouveroux Freddy Coignoul Jan Haelters Jacky Karpouzopoulos Sylvain Pezeril Daniel Desmecht 《PloS one》2014,9(12)
Bite-like skin lesions on harbour porpoises (Phocoena phocoena) have been suspected to be caused by grey seals (Halichoerus grypus), and a few field observations have been reported. Bite-like skin lesions observed on stranded animals were characterized by two main components: large flaps of loose or missing skin and blubber with frayed edges and puncture lesions. Definitive demonstration of predation by a grey seal was not reported so far in those stranded animals. In this study, five stranded porpoises with bite-like skin lesions were swabbed for genetic investigations. In addition, the head of a recently dead grey seal was used to mimic bite-like skin injuries on a porpoise carcass. Subsequently, the artificial skin injuries were swabbed, along with the gum of the seal used for inflicting them (positive controls). Total DNA was extracted from the swabs and was used to retrieve a fragment of mitochondrial DNA by PCR. Primers were designed to amplify a specific stretch of mitochondrial DNA known to differ between grey seals and porpoises. The amplicon targeted was successfully amplified from the positive control and from two of the stranded porpoises, and grey seal-specific mitochondrial DNA was retrieved from all those samples. We conclude that (1) it is possible to detect grey seal DNA from dead porpoises even after several days in seawater and (2) bite-like skin lesions found on dead porpoises definitively result from grey seals attacks. The attacks are most likely linked with predation although, in a number of cases, scavenging and aggressive behaviour cannot be excluded. 相似文献
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Emmanuelle Richard Jean-Michel Gaillard Sonia Saïd Jean-Luc Hamann François Klein 《Oecologia》2010,163(1):91-97
Many previous studies have pointed out that, when resources are limited, the potential for competition should be high among sympatric species that display overlaps in habitat and nutritional niches. However, reliable evidence of competition between red deer (Cervus elaphus) and roe deer (Capreolus capreolus) has not been yet reported for life history traits directly measuring performance such as body mass, reproduction, or survival. From long-term monitoring of deer populations in the reserve of La Petite Pierre (France), we measured the sex-specific responses of roe deer fawn body mass to changes in red deer density after accounting for possible confounding effects of date of shooting, climatic conditions, and roe deer density. As expected under the hypothesis of competition, red deer density in a given year had a marked negative influence on body mass of roe deer fawns born the same year and the following year. Fawn mass of roe deer males and females responded in similar ways to changes in red deer density. Our study provides the first evidence of a negative response of roe deer performance to high red deer density. 相似文献
899.
Lilli Anselm David W. Banner Jörg Benz Katrin Groebke Zbinden Jacques Himber Hans Hilpert Walter Huber Bernd Kuhn Jean-Luc Mary Michael B. Otteneder Narendra Panday Fabienne Ricklin Martin Stahl Stefan Thomi Wolfgang Haap 《Bioorganic & medicinal chemistry letters》2010,20(17):5313-5319
A series of (3R,4R)-pyrrolidine-3,4-dicarboxylic acid amides was investigated with respect to their factor Xa inhibitory activity, selectivity, pharmacokinetic properties, and ex vivo antithrombotic activity. The clinical candidate from this series, R1663, exhibits excellent selectivity against a panel of serine proteases and good pharmacokinetic properties in rats and monkeys. A Phase I clinical study with R1663 has been finalized. 相似文献
900.
Olivier Pible Claude Vidaud Sophie Plantevin Jean-Luc Pellequer Eric Qu��m��neur 《Protein science : a publication of the Protein Society》2010,19(11):2219-2230
The uranyl cation (UO22+) can be suspected to interfere with the binding of essential metal cations to proteins, underlying some mechanisms of toxicity. A dedicated computational screen was used to identify UO22+ binding sites within a set of nonredundant protein structures. The list of potential targets was compared to data from a small molecules interaction database to pinpoint specific examples where UO22+ should be able to bind in the vicinity of an essential cation, and would be likely to affect the function of the corresponding protein. The C‐reactive protein appeared as an interesting hit since its structure involves critical calcium ions in the binding of phosphorylcholine. Biochemical experiments confirmed the predicted binding site for UO22+ and it was demonstrated by surface plasmon resonance assays that UO22+ binding to CRP prevents the calcium‐mediated binding of phosphorylcholine. Strikingly, the apparent affinity of UO22+ for native CRP was almost 100‐fold higher than that of Ca2+. This result exemplifies in the case of CRP the capability of our computational tool to predict effective binding sites for UO22+ in proteins and is a first evidence of calcium substitution by the uranyl cation in a native protein. 相似文献