Coefficient of inbreeding

The coefficient of inbreeding (COI) is a number measuring how inbred an individual is. Specifically, it is the probability that two alleles at any locus in an individual are identical by descent from a common ancestor of the two parents. A higher COI will make the traits of the offspring more predictable, but also increases the risk of health issues. In dog breeding, it is recommended to keep the COI less than 5%, however in some breeds this may not be possible without outcrossing.