The genetic architecture of genome-wide recombination rate variation in allopolyploid wheat revealed by nested association mapping.

Recombination affects the fate of alleles in populations by imposing constraints on the reshuffling of genetic information. Understanding the genetic basis of these constraints is critical for manipulating the recombination process to improve the resolution of genetic mapping, and reducing the negative effects of linkage drag and deleterious genetic load in breeding. Using sequence-based genotyping of a wheat nested association mapping (NAM) population of 2,100 recombinant inbred lines created by crossing 29 diverse lines, we mapped QTL affecting the distribution and frequency of 102 000 crossovers (CO). Genome-wide recombination rate variation was mostly defined by rare alleles with small effects together explaining up to 48.6% of variation. Most QTL were additive and showed predominantly trans-acting effects. The QTL affecting the proximal COs also acted additively without increasing the frequency of distal COs. We showed that the regions with decreased recombination carry more single nucleotide polymorphisms (SNPs) with possible deleterious effects than the regions with a high recombination rate. Therefore, our study offers insights into the genetic basis of recombination rate variation in wheat and its effect on the distribution of deleterious SNPs across the genome. The identified trans-acting additive QTL can be utilized to manipulate CO frequency and distribution in the large polyploid wheat genome opening the possibility to improve the efficiency of gene pyramiding and reducing the deleterious genetic load in the low-recombining pericentromeric regions of chromosomes.

¿Qué quiere una madre? Comentario sobre Todo sobre mi madre, de Pedro Almodóvar / What does a mother? Review of All About My Mother by Pedro Almodóvar

El film de Almodóvar ha cobrado notoriedad a partir de obtener el premio Oscar en 2000. Se han elogiados sus hallazgos estéticos y actorales pero no siempre se ha advertido su carácter visionario en materia de neoparentalidades. Este trabajo da cuenta de esa dimensión, identificando la lógica contemporánea de los trasplantes y otras transformaciones del cuerpo, analizadas a la luz de la teoría performativa de Judith Butler, las modernas perspectivas de género, y la teoría psicoanalítica de Jacques Lacan. También a partir de las referencias a las artes plásticas, a la tragedia griega y al teatro contemporáneo como fuentes para pensar el problema más allá de los cánones tradicionales...

Almodóvar's film has gained notoriety when it obtained the Oscar prize in 2000. Public and critic praised its aesthetic and acting findings but not always warned his visionary character. This work gives account of that dimension, identifying the logic of contemporary transplants and other body transformations, analyzed in light of performative theory of Judith Butler, the modern gender perspectives, psychoanalytic theory of Jacques Lacan. Also from references to the visual arts, to Greek tragedy and contemporary theater as sources to think the problem beyond of traditional perspectives.

Nucleotide diversity maps reveal variation in diversity among wheat genomes and chromosomes.

BACKGROUND: A genome-wide assessment of nucleotide diversity in a polyploid species must minimize the inclusion of homoeologous sequences into diversity estimates and reliably allocate individual haplotypes into their respective genomes. The same requirements complicate the development and deployment of single nucleotide polymorphism (SNP) markers in polyploid species. We report here a strategy that satisfies these requirements and deploy it in the sequencing of genes in cultivated hexaploid wheat (Triticum aestivum, genomes AABBDD) and wild tetraploid wheat (Triticum turgidum ssp. dicoccoides, genomes AABB) from the putative site of wheat domestication in Turkey. Data are used to assess the distribution of diversity among and within wheat genomes and to develop a panel of SNP markers for polyploid wheat. RESULTS: Nucleotide diversity was estimated in 2114 wheat genes and was similar between the A and B genomes and reduced in the D genome. Within a genome, diversity was diminished on some chromosomes. Low diversity was always accompanied by an excess of rare alleles. A total of 5,471 SNPs was discovered in 1791 wheat genes. Totals of 1,271, 1,218, and 2,203 SNPs were discovered in 488, 463, and 641 genes of wheat putative diploid ancestors, T. urartu, Aegilops speltoides, and Ae. tauschii, respectively. A public database containing genome-specific primers, SNPs, and other information was constructed. A total of 987 genes with nucleotide diversity estimated in one or more of the wheat genomes was placed on an Ae. tauschii genetic map, and the map was superimposed on wheat deletion-bin maps. The agreement between the maps was assessed. CONCLUSIONS: In a young polyploid, exemplified by T. aestivum, ancestral species are the primary source of genetic diversity. Low effective recombination due to self-pollination and a genetic mechanism precluding homoeologous chromosome pairing during polyploid meiosis can lead to the loss of diversity from large chromosomal regions. The net effect of these factors in T. aestivum is large variation in diversity among genomes and chromosomes, which impacts the development of SNP markers and their practical utility. Accumulation of new mutations in older polyploid species, such as wild emmer, results in increased diversity and its more uniform distribution across the genome.

Disaster drill exercise documentation and management: are we drilling to standard?

INTRODUCTION: Medical errors are known to occur even in a controlled setting with adequate resources. The few studies on mass-casualty events and disaster exercises suggest errors may be amplified in these situations. We hypothesized that both the documentation and medical care provided during a pediatric disaster drill would be substandard when compared with routine care at the same institution. METHODS: Charts from the disaster exercise and matched charts from actual admitted patients were retrospectively reviewed for the presence of triage classification, allergies, weight, physical exam, vital signs, diagnosis, disposition time, disposition location, disposition instructions, and disposition vitals signs and for the appropriateness of diagnoses, medications, procedures, and disposition. Errors were quantified and classified into negligible, likely to cause temporary harm, or potential to cause admission or permanent harm. The drill charts were compared to actual charts by Fischer's Exact Test. RESULTS: Drill charts contained a significantly greater proportion of errors in regards to performance of procedures, administration of medication, and accuracy of diagnosis. Sixteen percent of these errors were judged as having the potential to cause permanent harm or admission. The exercise charts contained a significantly greater number of omissions in documentation in 9 of the 10 areas evaluated. DISCUSSION: Both the documentation and the quality of care provided during our exercise were deficient when compared with conventional care. Opportunities allowing providers to clearly document pertinent information, and linking of this documentation to relevant prompts and algorithms may minimize this potential for error.

Enhanced ADP-glucose pyrophosphorylase activity in wheat endosperm increases seed yield.

Yield in cereals is a function of seed number and weight; both parameters are largely controlled by seed sink strength. The allosteric enzyme ADP-glucose pyrophosphorylase (AGP) plays a key role in regulating starch biosynthesis in cereal seeds and is likely the most important determinant of seed sink strength. Plant AGPs are heterotetrameric, consisting of two large and two small subunits. We transformed wheat (Triticum aestivum L.) with a modified form of the maize (Zea mays L.) Shrunken2 gene (Sh2r6hs), which encodes an altered AGP large subunit. The altered large subunit gives rise to a maize AGP heterotetramer with decreased sensitivity to its negative allosteric effector, orthophosphate, and more stable interactions between large and small subunits. The Sh2r6hs transgene was still functional after five generations in wheat. Developing seeds from Sh2r6hs transgenic wheat exhibited increased AGP activity in the presence of a range of orthophosphate concentrations in vitro. Transgenic Sh2r6hs wheat lines produced on average 38% more seed weight per plant. Total plant biomass was increased by 31% in Sh2r6hs plants. Results indicate increased availability and utilization of resources in response to enhanced seed sink strength, increasing seed yield, and total plant biomass.