DNA profiling can be carried out cheaply and easily through a simple cheek swab. The profile gives the individual dog's alleles for at least 18 microsatellite sites. Since a dog inherits half of its DNA from its Sire and half from its Dam if, for example, marker one shows the sire as 100/104 and the dam as 102/108 the alleles of the offspring could be 100/102, 100/108, 102/104 or 104/108.
A DNA profile is simply a biological 'microchip' - it uniquely identifies any particular dog. The profile cannot be used for any other purpose such as identifying disease carriers or specific traits such as colour or size.
However in a breed with a very limited gene pool such as the Cesky Terrier, by using the information from the DNA Profile a breeder can select a sire that will increase heterozygosity in the subsequent litter. This is a more successful approach to the problem of maintaining genetic diversity than by 'out-crossing' to a dog that has no close relatives over three or even five generations, but that may, in fact, be genetically almost identical to the dam.
By utilising the information in the profile we can compare the genetic make-up of different dogs and, whenever possible, choose a mating that offers the possibility of some genetic diversity.
By comparing values at each point on the profile we can see how the genetic make-up of dogs differs. Cesky Terriers all have very similar profiles – even the different ‘lines’ cannot be distinguished. The very smallest amounts of diversity are important in this breed.
Utilising DNA profiling gives the breeder the choice both of increasing homozygosity in order to cement breed type, and of introducing genetic variation into an already homozygous line. Thus profiling is a simple means of maintaining genetic diversity whilst still maintaining breed type.
There are several different companies that offer DNA profiling, including Animal DNA Diagnostics