Biomedical subjects

Thomas Derrien

Publications and source records attributed to Thomas Derrien.

4 recordsLinked to original sources

PubMed2006

AutoGRAPH: an interactive web server for automating and visualizing comparative genome maps.

UNLABELLED: AutoGRAPH is an interactive web server for automatic multi-species comparative genomics analyses based on personal datasets or pre-inserted public datasets. This program automatically identifies conserved segments (CS) and breakpoint regions, assesses the conservation of marker/gene order between organisms, constructs synteny maps for two to three species and generates high-quality, interactive displays facilitating the identification of chromosomal rearrangements. AutoGRAPH can also be used for the integration and comparison of several types of genomic resources (meiotic maps, radiation hybrid maps and genome sequences) for a single species, making AutoGRAPH a versatile tool for comparative genomics analysis. AVAILABILITY: http://genoweb.univ-rennes1.fr/tom_dog/AutoGRAPH/. SUPPLEMENTARY INFORMATION: A description of the algorithm and additional information are available at http://genoweb.univ-rennes1.fr/tom_dog/AutoGRAPH/Tutorial.php.

Algorithms↗

PubMed2006

Coat colour in dogs: identification of the merle locus in the Australian shepherd breed.

BACKGROUND: Coat colours in canines have many natural phenotypic variants. Some of the genes and alleles involved also cause genetic developmental defects, which are also observed in humans and mice. We studied the genetic bases of the merle phenotype in dogs to shed light on the pigmentation mechanisms and to identify genes involved in these complex pathways. The merle phenotype includes a lack of eumelanic pigmentation and developmental defects, hearing impairments and microphthalmia. It is similar to that observed in microphthalmia mouse mutants. RESULTS: Taking advantage of the dog as a powerful genetic model and using recently available genomic resources, we investigated the segregation of the merle phenotype in a five-generation pedigree, comprising 96 sampled Australian shepherd dogs. Genetic linkage analysis allowed us to identify a locus for the merle phenotype, spanning 5.5 megabases, at the centromeric tip of canine chromosome 10 (CFA10). This locus was supported by a Lod score of 15.65 at a recombination fraction theta = 0. Linkage analysis in three other breeds revealed that the same region is linked to the merle phenotype. This region, which is orthologous to human chromosome 12 (HSA12 q13-q14), belongs to a conserved ordered segment in the human and mouse genome and comprises several genes potentially involved in pigmentation and development. CONCLUSION: This study has identified the locus for the merle coat colour in dogs to be at the centromeric end of CFA10. Genetic studies on other breeds segregating the merle phenotype should allow the locus to be defined more accurately with the aim of identifying the gene. This work shows the power of the canine system to search for the genetic bases of mammalian pigmentation and developmental pathways.

Journal Article↗

PubMed2005

Facilitating genome navigation: survey sequencing and dense radiation-hybrid gene mapping.

Accurate and comprehensive sequence coverage for large genomes has been restricted to only a few species of specific interest. Lower sequence coverage (survey sequencing) of related species can yield a wealth of information about gene content and putative regulatory elements. But survey sequences lack long-range continuity and provide only a fragmented view of a genome. Here we show the usefulness of combining survey sequencing with dense radiation-hybrid (RH) maps for extracting maximum comparative genome information from model organisms. Based on results from the canine system, we propose that from now on all low-pass sequencing projects should be accompanied by a dense, gene-based RH map-construction effort to extract maximum information from the genome with a marginal extra cost.

Animals↗

PubMed2004

CRH_Server: an online comparative and radiation hybrid mapping server for the canine genome.

UNLABELLED: CRH_Server is an on line Comparative and Radiation Hybrid mapping Server dedicated to canine genomics. CRH_Server allows users to compute their own RH data using the current canine RH map, and allows comparative dog/human mapping analyses. Finally, it suggests multiple options for storage and queries of the dog RH database. AVAILABILITY: http://idefix.univ-rennes1.fr:8080/Dogs/rh-server.html. SUPPLEMENTARY INFORMATION: All information is available at http://idefix.univ-rennes1.fr:8080/Dogs/help_rh-server.html.

Algorithms↗