On the Sniff breed page, Golden Retrievers show moderate genetic diversity: mean heterozygosity about 0.28, ranking 28th most genetically tight of 107 ranked breeds (n = 3,523 dogs in the atlas cohort).
Among ranked breeds, that diversity measure ranges 0.14 (least diverse) to 0.40 (most diverse). Higher means a more diverse gene pool on average; lower means more attention to recessive-risk testing is warranted, not that any one dog is doomed.
This is a breed-level population fingerprint from typed-backbone SNPs, not a pedigree coefficient of inbreeding (COI) for an individual dog, and not a health score. For the full dimensions and citations, see the Golden Retriever page.