Insertion of a truncated P-element of approximately 2.5kb into Su(H), in the region between -800bp and -500bp (the major transcription initiation site is set as 0).
Insertion of a 1.9kb P-element at nucleotide +71, coordinate +12 on the restriction map of the Su(H) region, coordinate 0 is the second chromosome breakpoint of Tp(3;2)AntpCtx.
Transposase induced phenotypic and molecular reversion demonstrates the P-element insertion is responsible for the mutant phenotype.