title: Retroviruses and transposable elements--which came first?
mesh_terms: D000818:Animals; D004251:DNA Transposable Elements; D004330:Drosophila / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D012190:Retroviridae / Q000235:genetics*
chemical_list: D004251:DNA Transposable Elements