Generating homozygous flies for two genes situated on the 2^nd and 3^rd chromosomes. There maybe situations with some project such as the NSF project where it will be advantageous to establish homozygous fly lines that contain two different transposed genes such as a reporter gene and an activator gene. The following is one strategy by which this can be achieved. It is recommended that this be done in bottles because the desired phenotypes represent a small fraction of the total possibilities. The balancer stock Sp/SM6a;Gl/TM3 will be used. The following describes a situation where the target gene (eg: TRE70w) is on the 2^nd and the activator (eg: Bello’s BN18 line {ED-tTA(w⁺)}) is on the 3^rd chromosome. To simplify the cross descriptions, ED-tTA(w⁺) will be abbreviated as tTA(w⁺)
 

Cross 1a. ¡¡ p(w+)/p(w+); +/+ x ¢¢ Sp/SM6a; Gl/TM3 m Select ¡¡ p(w+)/SM6a; +/TM3 (Curly, Stubble)

Cross 1b. ¡¡ +/+; tTA(w+)/tTA(w+) x ¢¢ Sp/SM6a; Gl/TM3 m Select ¢¢ +/Sp; tTA(w+)/Gl (Sternaplural, Glued)

Cross 2. ¢¢ +/Sp; tTA(w+)/Gl x ¡¡ p(w+)/SM6a; +/TM3 m Select ¢¢ p(w+)/Sp; tTA(w+)/TM3 (Sternaplural, Stubble)

Cross 3. ¢¢ p(w+)/Sp; tTA(w+)/TM3 x ¡¡ Sp/SM6a; Gl/TM3 m Select ¢¢ and ¡¡ p(w+)/SM6a; tTA(w+)/TM3 (Curly, Stubble)

Cross 4. ¡¡ p(w+)/SM6a; tTA(w+)/TM3 x ¢¢ p(w+)/SM6a; tTA(w+)/TM3 m Select ¢¢ and ¡¡ p(w+)/ p(w+); tTA(w+)/ tTA(w+) and establish fly line. (Straight winged, long bristles)