In recent years, DNA (deoxyribonucleic acid) has become a very popular method of identification in people. Fortunately, these advancements in genetic studies have also benefited the canine world.
Prior to DNA tests, determining the actual parents of a specific puppy was not an accurate science. People had to rely on the breeder’s records and honesty. Since dogs are in estrus (heat) for several days and multiple matings are possible, puppies within the same litter can have different fathers. This has led to some disputes and even lawsuits regarding parentage. Today, these disputes can be readily and accurately solved.
The basis of life is the chromosome. Every cell in a dog has 39 pairs of chromosomes. Each of these chromosomes is made up of various gene pairs, with each chromosome having a potential of 50,000 to 100,000 gene pairs. Every cell in a specific dog is exactly the same. However, cells of a different dog will have different genes. This variation between cells of different dogs is the reason for the variety between breeds and even between individual dogs. This variety is also the reason parentage can be determined.
The genetic makeup of a dog is referred to as the dog’s genotype. Despite having 50,000 to 100,000 gene pairs, research has found that comparing the same 10 gene pairs in each dog can differentiate between dogs. And, since all cells in a particular dog are the same, you only need cells from inside the mouth to perform a DNA profile. Even though parentage can be determined, the breed of the dog cannot. For example, if you have a dog and want to know if he is a purebred collie, DNA testing cannot give you the answer.
DNA and the American Kennel Club
Since 1998, the American Kennel Club (AKC) has used DNA testing to monitor dog breeding programs. Called the “DNA certification program,” submitting samples is voluntary, except in certain circumstances. The purpose of the DNA certification program is to eliminate all questions about parentage and to uniquely identify a specific dog.
Every genotype is unique. Each gene is made of two genes, one from the mother and one from the father. If the genotype of the mother is known, by comparing the suspected father’s DNA with the offspring’s, the true parentage can be determined.
To determine a dog’s DNA profile, a small bristle brush is used to gently scrape inside the mouth. Cheek cells are obtained on the swab and submitted for analysis. Results are typically available in 6 to 8 weeks at a cost of $40 per sample. So far, the AKC has collected and analyzed more than 16,000 samples.
Indications for a DNA Profile
Many breeders voluntarily submit samples of their sires, dams and offspring. This helps them give a guarantee to the buyer of the puppy and adds to their reputation. There are times, however, that the AKC requires DNA profiling in order to register a certain dog or puppies.
In addition to reviewing litter and dog records and checking dog identification, inspectors also collect DNA samples from litters and their sires or dams. If any discrepancies are found such as puppies not actually being a product of the dam or sire of record, litter registration is canceled or corrected. The AKC disciplines kennels that have more than one litter excluded within 3 years. If repeated problems occur, the AKC privileges may be withdrawn.
For more information about DNA testing and the American Kennel Club, visit www.akc.org.