Coat Colour Cocoa is also known as the Co Locus. Brown or chocolate coat colour in many mammalian species is frequently due to variants at the B locus or TYRP1 gene. Dogs have five different TYRP1 loss-of-function alleles, which explain the vast majority of dogs with a brown coat colour. The brown coat colour in French Bulldogs is also determined by a mutation in the HPS3 gene. The mutations in this gene produce brown pigment in the coat, nose and footpads of dogs. The pigment on nose and footpads is visible regardless the dog’s genotype of other loci. The phenotype coat colour depends on more mutations at other genes.
Mutations in the HPS3 gene create a brown pigment by partially disrupting the black pigment. Together with the B locus (TYRP1 gene), the Co Locus plays a part in eumelanin synthesis. The Co Locus produces a more darker brown coat colour compared to the B Locus. Cocoa puppy’s are often born with blue eyes which darken when the puppy’s get older.
Recently, breeders and genetic testing laboratories identified brown French Bulldogs that did not carry any of the known mutant TYRP1 alleles.
Some brown French Bulldogs did not carry any known mutations of the TYRP1 alleles was discovered lately.
Test specific information
Most coat colours and coat types are usually visible directly after birth.
The Turnaround Time (TAT) depends on various factors, such as the shipment time of your sample to the test location, the test method(s) and whether the tests are performed completely or partially by a Partner Lab or Patent owner.
The TAT of tests performed at our facilities is normally 10 working days after receipt of the sample at the testing laboratory (VHL, VHP or Certagen). For tests performed by a Partner Laboratory (so-called "partner lab test") or patent owner, the TAT is at least 20 working days after receipt of your sample. Because the shipment time to our Partner Labs or patent owner may vary due to factors we cannot influence, the mentioned 20 working days are therefore an estimate.
Sometimes it is necessary to re-run your sample. We call this a retest. In that case, the TAT will of course be extended.
Location of disease or trait
This DNA test is available for the following breeds: French Bulldog. Additional information is available in the Frequently Asked Questions (FAQ).
For this DNA test we accept the following materials: Blood EDTA, Blood Heparin, Swab, Tissue, Semen. Please contact Dr. Van Haeringen Laboratorium if you wish to submit other material as listed.
Coat colours and coat types are based on many genetic factors. For each factor, a separate test result will be returned.
Various genetic factors influencing coat colour and coat types are inherited in a dominant or recessive mode. Coat colours are influenced by a large number of genetic factors.
Severity of Disease
Factors influencing coat colour and coat types are usually not related to diseases.