Polymorphism in structure of the retrotransposable element 412 in Drosophila simulans and D-melanogaster populations

The structure of the 412 retrotransposable element was investigated in vari ous natural populations of D. melanogaster and D. simulans by a restriction enzyme analysis. We show that although the canonical structure of the 412 element was the same in both species, a high structural polymorphism existe d with various rearranged elements. A 412 family was thus composed of heter ogeneous copies of different sizes, with a large proportion of full-size co pies. D. simulans had more rearranged copies than D. melanogaster, with som e specific copies, such as a 5.6-kb BsrBI fragment, present in all populati ons of D. simulans. Full-size and rearranged copies were detected in both t he euchromatin and the heterochromatin, with many rearranged copies in D. s imulans, suggesting a recent mobilization of the 412 element in this specie s. (C) 1999 Elsevier Science B.V. All rights reserved.