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Muriel Davisson

Publications and source records attributed to Muriel Davisson.

5 recordsLinked to original sources
PubMed2006

Know thy mouse.

In science it is imperative that the basic reagents and materials are defined and uniform. Unlike chemical reagents, which are uniform over time, mice, like all living creatures, have an intrinsic genetic drive to change, with mutations accumulating over time leading to increasing genetic variation and phenotypic change. Such changes compromise the reproducibility of experimental data over time and place. The use of the mouse has expanded rapidly in recent years and many scientists who have turned to the mouse as a research model might be unaware of the profound impact of changes in genetic background. Here we discuss the sources of genetic change and strategies to reduce them with the idea of strengthening international genetic standards for inbred mice.

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PubMed2003

Mouse model of subretinal neovascularization with choroidal anastomosis.

PURPOSE: To characterize the phenotype and report a reliable genetic model of retinal angiogenesis and subretinal neovascularization in the mouse. METHODS: The mouse phenotype was characterized using ophthalmoscopy, fundus photography, fluorescein angiography, electroretinography, histology, gene sequencing, and linkage analysis. RESULTS: Scattered pink-gray retinal lesions were found on ophthalmoscopy and were confirmed to be subretinal neovascularization on fluorescein angiography. On histologic examination, outer plexiform retinal neovascularization with growth into the subretinal space was found as early as postnatal Day 15. On genetic analysis, homozygosity of the Vldlr mutation always segregated with the retinal angiogenesis, whereas normal and heterozygous mice had no neovascularization. The histologic studies 15 to 18 days consistently showed new outer plexiform neovascular vessels drawn to the subretinal space by 20 days, and by 30 to 50 days, subretinal hemorrhages and choroidal anastomoses were common. Mice by 8 months had increased vascularity of the iris and ciliary body. CONCLUSIONS: The Vldlr mutation in the mouse provides a good model for retinal angiogenesis and subretinal neovascularization. Finding a strong association between retinal angiogenesis and a very low density lipid receptor mutation is new, and study of lipid receptor physiology may broaden the understanding of retinal angiogenesis.

Animals↗
PubMed2002

Annotation of human chromosome 21 for relevance to Down syndrome: gene structure and expression analysis.

Down syndrome is caused by an extra copy of human chromosome 21 and the resultant dosage-related overexpression of genes contained within it. To efficiently direct experiments to determine specific gene-phenotype correlations, it is necessary to identify all genes within 21q and assess their functional associations and expression patterns. Analysis of the complete finished sequence of 21q resulted in annotated 225 genes and gene models, most of which were incomplete and/or had little or no experimental verification. Here we correct or complete the genomic structures of 16 genes, 4 of which were not reported in the annotation of the complete sequence. Our data include the identification of six genes encoding short or ambiguous open reading frames; the identification of three cases in which alternative splicing produces two structurally unrelated protein sequences; and the identification of six genes encoding proteins with functional motifs, two genes with unusually low similarity to their orthologous mouse proteins, and four genes with significant conservation in Drosophila melanogaster. We further demonstrate that an additional nine gene models represent bona fide transcripts and develop expression patterns for these genes plus nine additional novel chromosome 21 genes and four paralogous genes mapping elsewhere in the human genome. These data have implications for generating complete transcript maps of chromosome 21 and for the entire human genome, and for defining expression abnormalities in Down syndrome and mouse models.

Animals↗