Somatic mutation in the wings of Drosphila melanogaster females dysgenic due to P elements when reared at 29°C

The possibility of somatic mobilisation of P elements in Drosphila melanogaster was investigated. Flies, trans-heterozygous for the genetic markers mwh and flr 3 were obtained by crossing males containing transposition-competent P elements with females having M cytotype. The hybrid dysgenic flies were reared at 29°C and their wings examined for mutant clones. The frequency of mutant spots found on the wings of the female flies was significantly higher than that of female control flies. We postulate that this increase in frequency may be due to P element mobilisation at high temperature in the wing cells of dysgenic hybrids. This is in direct contrast to the large body of reasearch which indicates that P-transposition-mediated mutation is restricted to the germline.