Genomic DNA was prepared from whole unfractionated peripheral blood from Pteropus vampyrus bats. Using primers derived from the inferred interferon gene sequences and encoded for restriction enzyme cloning sites, the genes were PCR amplified from the genomic DNA. The forward and reverse primers encoded restriction sites for NheI and XhoI respectively, which allowed cloning of the full length gene into mammalian expression vector pcDNA3.1(+). The PCR program consisted of an initialization step at 94°C for 5 minutes, then 30 cycles of amplification consisting of denaturation at 94°C for 1 minute, annealing at 55°C for 30 seconds, and elongation at 72° for 1 minute. Amplification was followed by a final elongation step at 72°C for 5 minutes and samples held at 4°C. PCR was performed on a P × 2 Thermal Cycler from ThermoElectron Corporation (Waltham, MA).