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Servin B.,French National Institute for Agricultural Research | Faraut T.,French National Institute for Agricultural Research | Iannuccelli N.,French National Institute for Agricultural Research | Zelenika D.,Center National Of Genotypage | Milan D.,French National Institute for Agricultural Research
BMC Genomics | Year: 2012

Background: The release of the porcine genome sequence offers great perspectives for Pig genetics and genomics, and more generally will contribute to the understanding of mammalian genome biology and evolution. The process of producing a complete genome sequence of high quality, while facilitated by high-throughput sequencing technologies, remains a difficult task. The porcine genome was sequenced using a combination of a hierarchical shotgun strategy and data generated with whole genome shotgun. In addition to the BAC contig map used for the clone-by-clone approach, genomic mapping resources for the pig include two radiation hybrid (RH) panels at two different resolutions. These two panels have been used extensively for the physical mapping of pig genes and markers prior to the availability of the pig genome sequence.Results: In order to contribute to the assembly of the pig genome, we genotyped the two radiation hybrid (RH) panels with a SNP array (the Illumina porcineSNP60 array) and produced high density physical RH maps for each pig autosome. We first present the methods developed to obtain high density RH maps with 38,379 SNPs from the SNP array genotyping. We then show how they were useful to identify problems in a draft of the pig genome assembly, and how the RH maps enabled the problems to be corrected in the porcine genome sequence. Finally, we used the RH maps to predict the position of 2,703 SNPs and 1,328 scaffolds currently unplaced on the porcine genome assembly.Conclusions: A complete process, from genotyping of a high density SNP array on RH panels, to the construction of genome-wide high density RH maps, and finally their exploitation for validating and improving a genome assembly is presented here. The study includes the cross-validation of RH based findings with independent information from genetic data and comparative mapping with the Human genome. Several additional resources are also provided, in particular the predicted genomic location of currently unplaced SNPs and associated scaffolds summing up to a total of 72 megabases, that can be useful for the exploitation of the pig genome assembly. © 2012 Servin et al.; licensee BioMed Central Ltd.

Liang L.,Harvard University | Morar N.,Imperial College London | Dixon A.L.,Imperial College London | Lathrop G.M.,Center National Of Genotypage | And 3 more authors.
Genome Research | Year: 2013

Gene expression levels can be an important link DNA between variation and phenotypic manifestations. Our previous map of global gene expression, based on ∼400K single nucleotide polymorphisms (SNPs) and 50K transcripts in 400 sib pairs from the MRCA family panel, has been widely used to interpret the results of genome-wide association studies (GWASs). Here, we more than double the size of our initial data set with expression data on 550 additional individuals from the MRCE family panel using the Illumina whole-genome expression array. We have used new statistical methods for dimension reduction to account for nongenetic effects in estimates of expression levels, and we have also included SNPs imputed from the 1000 Genomes Project. Our methods reduced false-discovery rates and increased the number of expression quantitative trait loci (eQTLs) mapped either locally or at a distance (i.e., in cis or trans) from 1534 in the MRCA data set to 4452 (with <5% FDR). Imputation of 1000 Genomes SNPs further increased the number of eQTLs to 7302. Using the same methods and imputed SNPs in the newly acquired MRCE data set, we identified eQTLs for 9000 genes. The combined results identify strong local and distant effects for transcripts from 14,177 genes. Our eQTL database based on these results is freely available to help define the function of disease-associated variants. © 2013, Published by Cold Spring Harbor Laboratory Press.

Julier C.,French Institute of Health and Medical Research | Julier C.,University Paris Diderot | Julier C.,Center National Of Genotypage | Nicolino M.,University of Lyon | Nicolino M.,French Institute of Health and Medical Research
Orphanet Journal of Rare Diseases | Year: 2010

Wolcott-Rallison syndrome (WRS) is a rare autosomal recessive disease, characterized by neonatal/early-onset non-autoimmune insulin-requiring diabetes associated with skeletal dysplasia and growth retardation. Fewer than 60 cases have been described in the literature, although WRS is now recognised as the most frequent cause of neonatal/early-onset diabetes in patients with consanguineous parents. Typically, diabetes occurs before six months of age, and skeletal dysplasia is diagnosed within the first year or two of life. Other manifestations vary between patients in their nature and severity and include frequent episodes of acute liver failure, renal dysfunction, exocrine pancreas insufficiency, intellectual deficit, hypothyroidism, neutropenia and recurrent infections. Bone fractures may be frequent. WRS is caused by mutations in the gene encoding eukaryotic translation initiation factor 2 kinase 3 (EIF2AK3), also known as PKR-like endoplasmic reticulum kinase (PERK). PERK is an endoplasmic reticulum (ER) transmembrane protein, which plays a key role in translation control during the unfolded protein response. ER dysfunction is central to the disease processes. The disease variability appears to be independent of the nature of the EIF2AK3 mutations, with the possible exception of an older age at onset; other factors may include other genes, exposure to environmental factors and disease management. WRS should be suspected in any infant who presents with permanent neonatal diabetes associated with skeletal dysplasia and/or episodes of acute liver failure. Molecular genetic testing confirms the diagnosis. Early diagnosis is recommended, in order to ensure rapid intervention for episodes of hepatic failure, which is the most life threatening complication. WRS should be differentiated from other forms of neonatal/early-onset insulin-dependent diabetes based on clinical presentation and genetic testing. Genetic counselling and antenatal diagnosis is recommended for parents of a WRS patient with confirmed EIF2AK3 mutation. Close therapeutic monitoring of diabetes and treatment with an insulin pump are recommended because of the risk of acute episodes of hypoglycaemia and ketoacidosis. Interventions under general anaesthesia increase the risk of acute aggravation, because of the toxicity of anaesthetics, and should be avoided. Prognosis is poor and most patients die at a young age. Intervention strategies targeting ER dysfunction provide hope for future therapy and prevention. © 2010 Julier and Nicolino; licensee BioMed Central Ltd.

Center National Of Genotypage and Roche Molecular Systems | Date: 2012-12-19

The present application provides polynucleotides comprising 5-tails with sequence segments useful for the detection of target nucleic acid sequences, and methods for their use in detecting target nucleic acids. The polynucleotides are used to amplify a subsequence of a target nucleic acid in the presence of one or more ribonucleotides. The ribonucleotides are incorporated into amplification products at regular intervals complementary to the 5-tail sequence segments. Cleavage of amplification products at the bond immediately 3 to incorporated ribonucleotides produces detectably distinct fragments indicative of the presence or absence of a target nucleic acid.

Gandotra S.,University of Cambridge | Le Dour C.,University Pierre and Marie Curie | Bottomley W.,Wellcome Trust Sanger Institute | Cervera P.,University Pierre and Marie Curie | And 17 more authors.
New England Journal of Medicine | Year: 2011

Perilipin is the most abundant adipocyte-specific protein that coats lipid droplets, and it is required for optimal lipid incorporation and release from the droplet. We identified two heterozygous frameshift mutations in the perilipin gene (PLIN1) in three families with partial lipodystrophy, severe dyslipidemia, and insulin-resistant diabetes. Subcutaneous fat from the patients was characterized by smaller-than-normal adipocytes, macrophage infiltration, and fibrosis. In contrast to wild-type perilipin, mutant forms of the protein failed to increase triglyceride accumulation when expressed heterologously in preadipocytes. These findings define a novel dominant form of inherited lipodystrophy and highlight the serious metabolic consequences of a primary defect in the formation of lipid droplets in adipose tissue. Copyright © 2011 Massachusetts Medical Society.

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