1. Place one fly in a 0.5 ml eppendorf tube and squish the fly for 5-10 seconds with a pipette tip containing 50 ml of squishing buffer (10 mM Tris-HCl pH8.2, 1 mM EDTA, 25 mM NaCl, and 0.2 mg/ml Proteinase K).

2. Incubate at 25-37 °C for 20-30 minutes.

3. Inactivate the Proteinase K by heating to 95 °C for 1-2 minutes.

4. Store the DNA at 4 °C. Use 1 ml for a 10-15 ml PCR reaction. Program PCR themocycler for 28-30 cycles.