Retrotransposons (q.v.) of Drosophila existing as a family of closely related base sequences that code for abundant mRNAs. There are usually between 20 and 60 copia elements per genome. The actual number depends on the Drosophila strain employed. The copia elements are widely dispersed among the chromosomes, and the sites occupied vary between strains. Each copia element ranges in size from 5 to 9 kilobase pairs, and it carries direct terminal repeats about 280 base pairs long. Several Drosophila mutations have been found that result from the insertion of copia-like elements. See Chronology, 1985, Mount and Rubin.
Subjects: Genetics and Genomics.