IcelandEnvironmentGene-Environment InteractionGenetic Predisposition to DiseaseGenotypeEvolution, MolecularRisk FactorsBreedingModels, GeneticPanicumQuantitative Trait, HeritableWeaningGenetic PleiotropyTwin Studies as TopicHybrid VigorQuantitative Trait LociSocial EnvironmentPhenotypeCrosses, GeneticAnimal HusbandrySelection, GeneticGenetic VariationReceptors, Dopamine D4PoaceaeDiseases in TwinsEpistasis, GeneticCattleSerotonin Plasma Membrane Transport ProteinsTwinsBody WeightAllelesPhylogenyChromosome MappingTriticumReproductionPolymorphism, Single NucleotideModels, StatisticalSeasonsAnalysis of VarianceLife Change EventsRegression AnalysisPolymorphism, GeneticAnimal FeedGenetic MarkersModels, BiologicalMolecular Sequence DataLinear ModelsDirected Molecular EvolutionAmino Acid SequenceSpecies SpecificityBase SequenceSequence Analysis, DNA