TransgenesMice, TransgenicGene DosageMolecular Sequence DataBase SequenceDosage Compensation, GeneticPlants, Genetically ModifiedMutationPhenotypeAnimals, Genetically ModifiedMice, Inbred C57BLRats, TransgenicPromoter Regions, GeneticAmino Acid SequenceGene Expression RegulationRNA, MessengerGene ExpressionRibosomal ProteinsTranscription, GeneticCloning, MolecularGenesDisease Models, AnimalAllelesPlasmidsHeterozygoteDosage FormsPolymerase Chain ReactionGene DuplicationTranscription FactorsGenotypeGene Expression Regulation, DevelopmentalGene DeletionChromosome MappingHomozygoteUbiquitin ThiolesteraseCrosses, GeneticDNA-Binding ProteinsMice, KnockoutGenes, BacterialDNA PrimersGenes, FungalGene Expression Regulation, PlantX Chromosome InactivationDNATobaccoRestriction MappingSaccharomyces cerevisiaeX ChromosomeHaploinsufficiencyBlotting, SouthernDown SyndromeReverse Transcriptase Polymerase Chain ReactionPlant ProteinsCarrier ProteinsGreen Fluorescent ProteinsBacterial ProteinsSequence Analysis, DNAMultigene FamilyEscherichia coliTrisomyPhylogenyPlants, ToxicTransformation, GeneticChromosomes, Human, Pair 21Genes, ReporterNucleic Acid HybridizationGenes, RegulatorImmunohistochemistryExonsBlotting, NorthernSequence Homology, Amino AcidAneuploidyThiolester HydrolasesSequence Homology, Nucleic AcidGene AmplificationMice, Mutant StrainsBrainModels, GeneticArabidopsisIntronsNerve Tissue ProteinsCells, CulturedSequence DeletionSignal TransductionGene Expression ProfilingOrgan SpecificityMembrane ProteinsIn Situ Hybridization, FluorescenceGenetic VectorsDrosophila melanogasterLac OperonCell LineSuppression, GeneticNuclear ProteinsHomeodomain ProteinsBlotting, WesternRecombinant Fusion ProteinsDNA Mutational AnalysisDrosophila ProteinsGenes, Viral