Insertion of P{Sd.P} element has been accompanied by deletion of one half of the duplication during insertion.
RanGAPSd.tPa.1 does not cause segregation distortion of Rspi/Rspss. Segregation distortion is not seen RanGAPSd.tPa.1 flies in the presence of E(SD)1 or of the SD-5[R7] chromosome (E(SD)1, Rspi, M(SD)1, St(SD)1).