What is COI?
COI stands for Coefficient of Inbreeding. It measures the similarity of a genes within a dog derived from inbreeding between relatives in their ancestry tree. Calculating estimated COI is an integral part of any responsible breeding effort.
Why does it matter?
To put it simply, if a dog inherits higher than normal genetic similarities from their parents it leads to an increase in genetic mutation and health risks. On many levels, genetic similarities are what distinguish breeds and give pups their own unique set of characteristics. Inbreeding has occurred in all purebred dogs dating back to their original ancestors. Mating a grandfather with a granddaughter was common practice in the early days of selective breeding to attempt to retain traits within a family lineage. This was in the 1800’s before an understanding of genetics existed.
Given the established makeup of the dog population today, there’s no justification for any inbreeding since breeds with certain traits have become well defined. In 2022, mating family members is widely recognized as highly irresponsible. Breeders of purebred dogs should seek to increase genetic diversity within the breed, lowering COI, because it leads to an increase in duration and quality of life. In puppies within their expected litter and future generations!
Combining genetics, COI, and health risk
COI calculates the likelihood of having duplicate dominant or recessive genes inherited by a dog from their parents. Genetic pairings, which bring the highest health risks, occur when a dog inherits the same copy of a recessive, or dominant gene from each parent for a harmful trait. This happens because recessive genes, which haven’t been bred out, are paired with the same copy from both parents and activated. Common examples of increased health risks for diseases are cancer, hip dysplasia, and breed-specific genetic vulnerabilities to certain conditions. Other drawbacks can include lower fertility rates and genetically driven mental health issues that show up in the form of anxiety or aggression.
The best way to protect against health risks and future mutations is to breed dogs from separate ancestral backgrounds, increasing genetic variation in the gene pool of an individual dog and breed. If this practice is adhered to responsibly by breeders, collective COI will decrease among each breed over time as genetic diversity increases due to our ability to better select a mate with help of DNA technology. Proactively preventing health problems in our precious pups leads to a higher quality of life for our dogs and their families.
Coefficient of Inbreeding is a critical factor in determining the appropriateness of mating particular dogs. The degree to which risk can be mitigated will vary among breeds based on historical inbreeding practices. Regardless of breed, we humans planning for litters should strongly consider COI when selecting a partner in combination with other phylogenetic traits that can be seen with the naked eye.
How is COI Measured?
There are different scales and rating methods to measure COI, so a numerical rating for one method should not be compared to another. The most relevant commonly practiced method used today is the Hardiman scoring system. This is more accurate than other historical measurements, but we feel unnecessary to explain because in 2022 there is a clear cut better solution.
The issue with Hardiman’s method as a base, stems from a limitation on how far back ancestry can be traced – this limits the results and can lead to inaccurate analysis. Recently, DNA testing has become available to measure the exact COI of a dog and the estimated COI for the litter of a prospective mating pair. One popular company doing this genetic profiling is Embark.
Embark is developing a relationship with the OFA, Orthopedic Foundation for Animals, to certify that a dog’s results are indeed their own authentic profile and not another dog. At Wise Woofs, feel every canine breeding candidate should be genetically tested and enrolled in matchmaking programs as standard practices moving forward. In addition to providing the most accurate measurement of COI, Embark currently tests for over 200 genetic variants that have been associated with disease. They have provided breeders a more precise way to prevent genetically driven disease and ensuring the healthiest possible outcome for their litters.
Another advantage of DNA testing is it can performed via a blood draw on young puppies. Specific COI among pups with a litter will vary. This helps identify breeding candidates with strong genetic profiles for the future while having the ability to rule out, or address any genetic issues that may be apparent through DNA analysis.
This type of testing absolutely rocks! Wise Woofs proudly supports them and encourage everyone to have their dog’s DNA profiled to learn all sorts of cool facts about your specific woof – Whether it be for breeding or not.
