Personal communication from: Ruben D. Artero, Valencia University (Universitat de Valencia) To: Bloomington Drosophila Stock Center Subject: no reversions for l(2)0103801038 and l(2)0712907129 Information communicated: "I am sending this message to report our results with two P element insertions from the Berkeley Drosophila genome project after transposase movilize them. 1. P976 (l(2)01038). After movilization we did not recover any viable revertant and concluded that there must be another lethal in this chromosome (the strain behaves as lethal). The same result was obtained, independently, by Gerrit Begemann (Marek Mlodzik's group; personal communication). We are about to 'clean' this insertion. 2. P2336 (l(2)07129). We made this movilization at the same time as the one for P976 but we did not recover any revertant at all. Maybe there is some problem with this insertion? (we could not plasmid rescue this strain either) Both strains are kept here since three years ago,more or less. We hope this could be of interest for the Drosophila genome project."