The Genomic Diversity Score is a genomic tool developed by the Australian Wagyu Association (AWA) to help Fullblood Wagyu breeders monitor and manage genetic diversity within their herds.
Calculated using genomic SNP (Single Nucleotide Polymorphism) data, the score measures how genetically similar or different an individual registered Japanese Black Fullblood animal is compared to the current AWA recorded Fullblood breeding population. The Genomic Diversity Score provides breeders with an additional tool to make informed mating decisions that can help minimise inbreeding and maintain long-term herd sustainability.
Important: The Genomic Diversity Score is only calculated for Japanese Black Fullblood animals with a genomic SNP profile. Crossbred animals are not assessed because the introduction of genetics from other breeds naturally creates high levels of genetic diversity.
Why Genetic Diversity Matters in Wagyu
The AWA Fullblood Wagyu population originates from a relatively small number of animals imported from Japan. As a result, many modern Fullblood pedigrees share common ancestors.
While selective breeding has delivered significant genetic progress, maintaining adequate genetic diversity remains important to:
- Reduce the rate of inbreeding within the population.
- Preserve fertility and reproductive performance.
- Maintain long-term herd resilience.
- Ensure breeders have access to a broader range of genetic options in future generations.
The Genomic Diversity Score helps identify animals that are either closely related to, or genetically distinct from, the current breeding population.
How the Genomic Diversity Score Is Calculated
The score is generated by comparing an individual animal’s genomic profile against a reference population. The reference population is set as the last five calendar years of registered Fullblood Japanese Black Females, which will become approximately 70% of the future breeding population.
Using a continuously updated reference population ensures the score remains relevant to the genetics currently being used across the industry.
By comparing an animal’s SNP profile against this breeding population, the system determines how closely related that animal is to the average future breeding female.
Understanding Genomic Diversity Score
The Genomic Diversity Score is a relative measure of genetic similarity to the reference population.
Low Diversity Scores (25 and below)
Animals with low diversity scores are more genetically similar to the average Japanese Black population. These animals are likely to carry genetics that are already well represented within the breed.
Average Diversity Scores (around 50)
Animals with scores around 50 represent a moderate level of genetic diversity relative to the Japanese Black population. The average Fullblood Wagyu sire typically has a Genomic Diversity Score close to 50.
High Diversity Scores (75 and higher)
Animals with high diversity scores are more genetically distinct from the current Japanese Black population. These animals may provide opportunities to introduce less common genes into breeding programs and help manage future inbreeding levels.
Selecting a sire that is relatively unrelated to the female herd can help reduce the level of inbreeding in future progeny.
Limitations
At present, Genomic Diversity Scores are only available for Japanese Black Fullblood Wagyu animals with a genomic SNP profile.
The score is not currently calculated for:
- Purebred Wagyu
- Wagyu-content animals
- Red Wagyu (Akaushi)
This is because there are currently insufficient reference populations to generate meaningful and reliable diversity predictions for these groups.
Key Takeaway
The Genomic Diversity Score is a practical genomic tool that enables Fullblood Wagyu breeders to assess how closely an animal is related to the current breeding population. When used alongside pedigree information, genomic data, and selection indexes, it can support breeding decisions that balance genetic progress with the long-term sustainability of the Australian Wagyu herd.
