Arthritis, RheumatoidEnvironmentGenotypeArthritisGenetic VariationDisease SusceptibilityGenetic Predisposition to DiseaseArthritis, ExperimentalPhenotypeBiological EvolutionEcosystemArthritis, InfectiousPolymorphism, Single NucleotideSynovial MembranePasseriformesArthritis, JuvenileAntirheumatic AgentsModels, GeneticGenetics, PopulationPopulation DynamicsPolymorphism, GeneticAllelesSelection, GeneticSynovial FluidReproductionRheumatoid FactorGenetic FitnessHaplotypesArthritis, PsoriaticGene FrequencyBody SizeJointsClimateGene-Environment InteractionGeneticsSeasonsCase-Control StudiesSpecies SpecificityAdaptation, PhysiologicalModels, BiologicalArthritis, ReactiveHLA-DRB1 ChainsGeographyTemperatureGenome-Wide Association StudySynovitisOsteoarthritisLinkage DisequilibriumHLA-DR AntigensStochastic ProcessesGenetic MarkersBiodiversityTime FactorsMethotrexateAutoantibodiesPopulation DensityGenetic LinkageChromosome MappingSeverity of Illness IndexBlood SedimentationAutoimmune DiseasesMolecular Sequence DataAnalysis of VarianceMice, Inbred DBATumor Necrosis Factor-alphaLupus Erythematosus, SystemicPolymerase Chain ReactionMutationSulfasalazineImmunoglobulin GGenome, HumanRheumatoid NoduleMetacarpophalangeal JointSequence Analysis, DNAGold Sodium ThiomalatePeptides, CyclicHLA-DQ AntigensMicrobial Sensitivity TestsArthrographySpondylitis, AnkylosingEpistasis, GeneticRisk FactorsRheumatologyQuantitative Trait LociGenetic Association StudiesGenetic LociRheumatic DiseasesMicrosatellite RepeatsCohort StudiesWrist JointBase SequenceTreatment OutcomeHLA-DQ beta-ChainsHLA-DR4 AntigenAntibodies, MonoclonalDisease Models, AnimalCrohn DiseaseEuropean Continental Ancestry GroupGenetic TestingHLA Antigens