Avian leukosis virusAvian LeukosisAlpharetrovirusChickensAvian Sarcoma VirusesBursa of FabriciusAvian ProteinsChick EmbryoReceptors, VirusPoultry DiseasesReticuloendotheliosis virusSarcoma, AvianQuailGenes, polCoturnixDNA, ViralGenes, envProvirusesGenes, gagHemangiomaAvian myeloblastosis virusVirus ReplicationDefective VirusesMolecular Sequence DataHerpesvirus 2, GallidRNA, ViralMarek DiseaseGenes, ViralLymphomaCell LineRepetitive Sequences, Nucleic AcidEndogenous RetrovirusesRNA-Directed DNA PolymeraseBase SequenceViral InterferenceCulture TechniquesTenosynovitisEnzootic Bovine LeukosisRecombination, GeneticRetroviridaeVirus IntegrationOncogenesCytopathogenic Effect, ViralCell Transformation, NeoplasticCell Transformation, ViralBirdsRetroviridae ProteinsAntigens, ViralFibroblastsViral Envelope ProteinsAmino Acid SequenceGenetic VectorsNucleic Acid HybridizationRNA VirusesSpecies SpecificityCells, CulturedViral ProteinsHelper VirusesSequence Analysis, DNAVaccinia virusGenome, ViralDNA PrimersCloning, MolecularVirus CultivationPolymerase Chain ReactionHistiocytic SarcomaSequence Homology, Nucleic AcidMutationChina