• DNA Profiling & 
    Parentage Verification
    We offer DNA profiling which can be used to confirm parentage or the identity of your horse.
    Find out how
  • Genetic Diagnostic Testing
    We offer testing for known mutations that cause genetic disorders. This can be used to prevent the birth of a foal affected by one of these disorders.
    Find out how
  • Coat Colour &
    Pattern Testing
    Our coat colour or pattern testing can be used as an aid for selection to produce a foal of a particular colour.
    Find out how
  • Infectious Disease Testing
    The EGRC is currently executing a trial of PCR detection of the pre-breeding panel pathogens. This service is for veterinarians only.
    Find out how


The pearl mutation dilutes both red and black pigment if two copies are present

Alternate names

Barlink Factor



Breeds known to carry this mutation

Quarter Horses and related breeds, Paint Horses, and Spanish breeds such as Andalusian and Lusitanos

Inheritance pattern

Autosomal recessive


Pearl is a rare dilution usually only observed in Quarter horses and Spanish horse breeds. This mutation is recessive so the horse must have two copies to express the effect. Horses carrying two copies of pearl (Prl/Prl) will have a lightened coat, mane, and tail, in addition to bright eye colours. Pearl also interacts with Cream dilution to produce pseudo-double cream dilute phenotypes. This is because the Pearl mutation is found in the same gene as Cream dilution.

Interpretation of results

n/n: Horse does not carry the pearl dilution allele.

n/Prl: Horse is heterozygous for the pearl dilution allele. The horse will not have a diluted coat but has a 50% chance of passing on pearl to its offspring.

Prl/Prl: Horse has two copies of the pearl dilution allele. It will have a diluted coat and will pass the pearl gene onto all its offspring.


Holl et al. A candidate gene approach identifies variants in SLC45A2 that explain dilute phenotypes, pearl and sunshine, in compound heterozygote horses. Animal Genetics 2019; 50:271-4. doi: 10.1111/age.12790

Powered by © 2023 Racing Australia Limited (ACN 105 994 330)