Chromosome carries both H{}A15.rev (an internally deleted hobo element in the first intron of alt, 1188bp from the first alt transcription start site, oriented in the sense direction of the alt transcription unit) and the Doc{}A15 insertion (also within alt) that was present on the progenitor chromosome. This chromosome was selected as a suppressor of the nondisjunction phenotype caused by the effect of the Doc{}A15 insertion on Mps1 gene function. mRNA expression analysis of 0-2 hour embryos from eggs laid by females homozygous for this double insertion chromosome show that expression of the neighboring downstream genes Mps1 and CG7523 is restored relative to the Doc{}A15 progenitor, while silencing of the alt gene persists in the double insertion chromosome.