Talking welfare: the importance of a common language.

Ontologies describing mouse phenotypes and pathology are well established and becoming more universally used (Smith and Eppig in Mamm Genome 23:653, 2012; Scofield et al. in J Biomed Semant 4:18, 2013). However, the language used to describe and disseminate cage-side observations is less well developed. This article explores the hurdles to unifying a language and terminology, and introduces our initial attempt to do so.

Tet-Transgenic Rodents: a comprehensive, up-to date database.

Here we introduce the "Tet-Transgenic Rodents" database, documenting most of the published Tet-transgenic mouse lines generated in the past 2 decades. Aside from the >500 mouse lines listed, it also includes the first of the recently reported Tet-transgenic rat models. Since the Tet technology comprises two essential components, a cis-acting promoter (Ptet) and a trans-acting transactivator, the database has been organized accordingly. One section of the database summarizes the different transgenic mouse lines carrying mostly tissue specific promoters driving the Tet transactivator. Another section covers transgenic mouse lines carrying responder transgenes under Ptet control. The few existing rat transgenic lines are listed correspondingly. It is the purpose of this database to facilitate the repeated use of preexisting, validated transgenic lines as a shortcut for further research.

High-throughput sorting of mosquito larvae for laboratory studies and for future vector control interventions.

BACKGROUND: Mosquito transgenesis offers new promises for the genetic control of vector-borne infectious diseases such as malaria and dengue fever. Genetic control strategies require the release of large number of male mosquitoes into field populations, whether they are based on the use of sterile males (sterile insect technique, SIT) or on introducing genetic traits conferring refractoriness to disease transmission (population replacement). However, the current absence of high-throughput techniques for sorting different mosquito populations impairs the application of these control measures. METHODS: A method was developed to generate large mosquito populations of the desired sex and genotype. This method combines flow cytometry and the use of Anopheles gambiae transgenic lines that differentially express fluorescent markers in males and females. RESULTS: Fluorescence-assisted sorting allowed single-step isolation of homozygous transgenic mosquitoes from a mixed population. This method was also used to select wild-type males only with high efficiency and accuracy, a highly desirable tool for genetic control strategies where the release of transgenic individuals may be problematic. Importantly, sorted males showed normal mating ability compared to their unsorted brothers. CONCLUSIONS: The developed method will greatly facilitate both laboratory studies of mosquito vectorial capacity requiring high-throughput approaches and future field interventions in the fight against infectious disease vectors.

[Study on recent status of development of genetically modified animals developed not for food purposes].

Genetically modified (GM) animals can be classified into two groups, those developed for food purposes and those developed not for food purposes. We investigated the recent status of development of GM animals developed not for food purposes. Among the GM animals developed not for food purposes, GM fish, chickens, and pigs were selected because many articles have been published on these organisms. Relevant articles published between 2008 and 2011 were surveyed using PubMed and transgenic fish, chicken, or pig as keywords. Then, studies on organisms that could potentially contaminate the food chain with products from these GM animals were selected and analyzed. Fifteen articles on GM fish were found. These articles were classified into four categories: bioreactor (n = 4), resistance to microorganisms (n = 6), resistance to environmental stresses (n = 1), and detection of chemicals (n = 4). Zebrafish were used in 8 of the articles. Six, three, and three articles were reported from Taiwan, Canada and China. Seven articles on GM chickens were found. These articles were classified into two categories: bioreactor (n = 5), and resistance to pathogens (n = 2). Two articles were reported from Japan and Korea, each. As for GM pigs, 43 articles were found. These articles were classified into three categories: xenotransplantation (n = 36), bioreactor (n = 6), and environmental cleanup (n = 1). Nineteen, seven, six, and five articles were reported from USA, Germany, Korea and Taiwan, respectively. Understanding the recent development of GM animals produced not for food purpose is important for assuring the safety of food.

Sepsid even-skipped enhancers are functionally conserved in Drosophila despite lack of sequence conservation.

The gene expression pattern specified by an animal regulatory sequence is generally viewed as arising from the particular arrangement of transcription factor binding sites it contains. However, we demonstrate here that regulatory sequences whose binding sites have been almost completely rearranged can still produce identical outputs. We sequenced the even-skipped locus from six species of scavenger flies (Sepsidae) that are highly diverged from the model species Drosophila melanogaster, but share its basic patterns of developmental gene expression. Although there is little sequence similarity between the sepsid eve enhancers and their well-characterized D. melanogaster counterparts, the sepsid and Drosophila enhancers drive nearly identical expression patterns in transgenic D. melanogaster embryos. We conclude that the molecular machinery that connects regulatory sequences to the transcription apparatus is more flexible than previously appreciated. In exploring this diverse collection of sequences to identify the shared features that account for their similar functions, we found a small number of short (20-30 bp) sequences nearly perfectly conserved among the species. These highly conserved sequences are strongly enriched for pairs of overlapping or adjacent binding sites. Together, these observations suggest that the local arrangement of binding sites relative to each other is more important than their overall arrangement into larger units of cis-regulatory function.

An algorithm for the identification of genetically modified animals.

The diffusion of genetically modified (GM) animals has generated a demand for accurate and unique identification to assure compliance with relevant national and international legislation. Individual identification of GM animals is essential to improve safety and traceability, as well as to fulfill the present and future expectations of producers, consumers, and authorities.

[A comprehensive form for the standardized characterization of transgenic rodents: genotype, phenotype, welfare assessment, recommendations for refinement]. / Umfassendes Formular zur strukturierten Charakterisierung gentechnisch veränderter Tierlinien.

When "creating" transgenic mouse strains it is not possible to predict their phenotype with certainty, particularly not with respect to welfare. The generation of models for (human) diseases deliberately implies a compromised health ranging from minor (clinically inapparent) to lethal. To ensure animal welfare requirements and apply the criteria of the 3R, a careful phenotype characterisation and welfare assessment has to be done routinely for each newly produced strain, at individual and strain level, starting by the standardised monitoring of founders and their consequent generations. A comprehensive form has been developed for a standardised characterisation of transgenic mouse strains. It is subdivided into basic and detail information. It can be kept up to date continuously in the form of a computerised database, incorporating growing knowledge and experience of the strain. Basic information mainly serves the requirements of housing and breeding facilities as well as the authorities in view of animal welfare measures, detail information mainly serves the interests of research and efficiency.