Sequence encoding the wild-type bicistronic wrm locus (encoding both wrm1 and wrm2 open reading frames) has been introduced into the attP site in TI{TI}wrm-ΔattP reconstituting a wild-type wrm locus. A loxP site and a Disc\RFPDsRed(T1).3xP3.cHa marker remains downstream of the inserted sequence.