The Optimal Selection Genetic Health Index (GHI) describes the relative health level of an individual dog’s genetic makeup in relation to previously tested dogs in the Optimal Selection database. This single number takes into account disease test results, the severity of the disease findings, as well as measured genetic diversity for that individual, obtained by examining over 1,800 locations spread over all chromosomes. The average dog has a GHI value of 100 - the healthier the dog, the higher the index.
NOTE:: The GHI value of a dog should not be used for breeding selections by itself, as mating of two dogs with a high GHI will not necessarily lead to healthier offspring. The Breeder Tool is designed to evaluate the genetic match between individuals, and provides a calculated projected GHI of the offspring to give breeders an easy way to compare possible mates to optimize the health and diversity of the litter.
Coefficient of inbreeding (COI), also known as coefficient of relationship, is a method of evaluating the degree of relatedness of two individuals based on pedigree records, not DNA testing. As a result, the COI is exactly the same for all puppies from a particular mating. Although genetic recombination in mammalian breeding is unpredictable, COI does not take into consideration the actual DNA inherited by an individual or variation between individuals within litters, nor does it correct for inaccuracies or unknowns in pedigree. DNA testing for diversity is individual-specific and can therefore be more sensitive, identifying opportunities for gains in diversity that could not otherwise be discerned by COI calculations.
Haplotype diversity refers to a form of DNA testing wherein sets or patterns of DNA markers are considered in breeding. This is popularly used in humans for the Y, or male chromosome, and is sometimes used in dogs. We believe evaluating genetic diversity across all markers and chromosomes is a more holistic, comprehensive approach to genetic diversity, although there are certainly conditions in which haplotype testing is more appropriate. The Optimal Selection Genetic Health Index provides all the information derived from an individual’s diversity and health evaluation in one easy to understand value, and in combination with the Breeder Tool, can allow breeders to make smarter breeding decisions. Unlike most haplotype testing, it does not require consultation with a genetics expert for result interpretation.
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