There are other types of microsatellites that differ from the types mentioned here but they follow the same general pattern as the two and four nucleotide pattern which are the types most widely used for fingerprinting. This is analogous to a listing of the genes and alleles for a red-factored blue merle, i.e. BbMm . Barring some rare change or mutation , all of the alleles present at each locus in an individual can be traced back to the parents. Because there are multiple alleles known for each locus, and many loci are used, an incredible number of variations are possible and the chances that any two individuals would have the same profile are almost non-existent. The DNA fingerprinting process begins by collecting a tissue sample from the dog.
Blood draw or check swabs are two commonly used techniques to collect samples for DNA extractions.
In one or two hours, millions of copies of only selected microsatellites are produced from DNA from a tissue sample of the donor dog. The dog's DNA serves as a template for the duplication process. Any tissue that contains the nucleus of cells can provide the chromosomes to serve as templates. The PCR process is necessary to insure that enough material is present for detection and analysis. Following the duplication process, the microsatellite alleles are separated in a process called electrophoresis.