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, primerbinding
sites were selected to amplify specific short fragments of
DNA, because of degradation due to gelatin processing.