Transposable element insertion patterns as test of contamination of a Drosophila melanogaster inbred line.

A highly inbred line of Drosophila melanogaster, stable for the insertion pattern of the transposable elements copia and mdg1, was experimentally contaminated by flies from another line. We show that the alien genome income is clearly detectable by the changes induced in the insertion profiles of transposable elements, even twenty generations later.