title: Long-range chromosomal engineering is more efficient in vitro than in vivo.
abstract: Cre/LoxP mediated chromosomal engineering in embryonic stem (ES) cells has a variety of applications, including the creation of model systems for studying aneuploidy. Targeted meiotic recombination (TAMERE) was proposed as a high efficiency in vivo alternative to effect Cre-mediated recombination, in which Cre recombinase under control of the Synaptonemal Complex 1 promoter is expressed during male meiosis in transgenic mice. TAMERE has been successfully used with LoxP sites up to 100 kb apart. We tested TAMERE for a chromosome engineering application in which LoxP sequences were integrated into sites 3.9 Mb apart on the same (cis) or opposite (trans) copies of mouse Chromosome 16 (MMU16). TAMERE was ineffective in generating either a deletion or a translocation in vivo. The TAMERE method may be of limited use for large genomic rearrangements. The desired translocation was achieved with an in vitro method that can be used in any ES cell line. Mice produced from the reciprocal duplication/deletion of MMU16 in a region homologous to human chromosome 21 provide models that are useful in studies of Down syndrome.
authors.affiliation: Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
authors.forename: Lisa E
authors.initials: LE
authors.lastname: Olson
authors.forename: Jason
authors.initials: J
authors.lastname: Tien
authors.forename: Sarah
authors.initials: S
authors.lastname: South
authors.forename: Roger H
authors.initials: RH
authors.lastname: Reeves
mesh_terms: D000818:Animals; D002460:Cell Line; D002875:Chromosomes; D003433:Crosses, Genetic; D003434:Crossing Over, Genetic; D004268:DNA-Binding Proteins; D004195:Disease Models, Animal; D004314:Down Syndrome / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000235:genetics; D017930:Genes, Reporter; D005818:Genetic Engineering; D006801:Humans; D066298:In Vitro Techniques; D019426:Integrases / Q000235:genetics; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D009687:Nuclear Proteins / Q000235:genetics; D008249:Protein-Lysine 6-Oxidase / Q000235:genetics; D013234:Stem Cells; D014178:Translocation, Genetic
chemical_list: D004268:DNA-Binding Proteins; D016326:Extracellular Matrix Proteins; D009687:Nuclear Proteins; C489754:Sycp1 protein, mouse; C077112:Lox protein, mouse; D008249:Protein-Lysine 6-Oxidase; C045073:Cre recombinase; D019426:Integrases