Test variant should be c.880G>A. Note: In the initial study that identified the causal genetic variant, researchers did not find this variant in other Golden Retrievers, suggesting that it may be limited to a specific line or is at very low frequency in the population. Research to investigate the allele frequency in the Golden Retriever population is on-going at the VGL. Testing for this variant can assist veterinarians with diagnosis and helps breeders identify carriers among breeding stock to select appropriate mates that will reduce the risk of producing affected offspring. To avoid the possibility of producing affected puppies, matings between known carriers should be avoided. Dogs who genotype CMS/CMS should be clinically evaluated. [from VGL, 2020]