Many primers have been published based on both mitochondrial and nuclear genes to trace either bovine or porcine DNA in a variety of food products. In this experiment, to detect the presence of small amounts of DNA in gelatin, primers were selected from conserved regions of mitochondrial genes (cytochrome b). The high copy number of mitochondrial DNA per cells and the probability of their survival under different processing conditions ensure amplification of the expected PCR products even in samples containing small amounts of DNA (Rodriguez et al., 2004). Furthermore, primer-binding sites were selected to amplify specific short fragments of DNA, because of degradation due to gelatin processing.