Occurrence of P element in natural populations of Drosophila melanogaster in

Using PCR and sequencing we have demonstrated the presence of P elements in genomes of Drosophila melanogaster from natural populations of Ukraine. The degree of gonadal reduction revealed indirectly indicates low or, in some cases, zero activity of the mobile element in the inspected natural populations of Drosophila. All studied populations have been found to represent the M’ cytotype. In this study, we have shown for the first time that P element, absent two decades ago, has invaded Ukrainian populations of Drosophila melanogaster. This invasion is part of the worldwide expansion of P element in Drosophila melanogaster. In Ukraine, an initial stage of the invasion has been suggested to occur, and further evolution of the M’ cytotype into P cytotype is expected.