Twinning, MonozygoticGenetic DeterminismCloning, OrganismCloning, MolecularMolecular Sequence DataBase SequenceAmino Acid SequenceSequence Homology, Amino AcidDNA, ComplementaryGenes, BacterialEscherichia coliRestriction MappingSequence AlignmentPlasmidsSequence Homology, Nucleic AcidSequence Analysis, DNARecombinant ProteinsRNA, MessengerGene LibraryDNAChromosome MappingDNA Restriction EnzymesGenesBlotting, SouthernDNA, BacterialGene ExpressionBlotting, NorthernNucleic Acid HybridizationPolymerase Chain Reaction