During the last decades, a large number of scientific publications have described the genetic principles of coat colour and coat variation. Coat colours and coat variations are influenced by many hereditary factors. The DNA-tests are based on physiological effects in the body, in which the production and distribution of pigments result in many coat colour variants. In several cases, the coat colour of an animal may only be decided using DNA-tests.
The Silver gene (SILV gene), also called premelanosome protein (PMEL17 gene) is responsible for Merle. This gene is also known as M-Locus. Merle only dilutes eumelanin (black) pigment; dogs with two copies of the allele e (homozygous e/e) at E-Locus have no black pigment, thus do not express merle. Merle is an incompletely dominant coat color pattern characterized by irregularly shaped patches of diluted pigment and solid color. Blue and partially blue eyes are typically seen with merle, and merle dogs often have a wide range of auditory and ophthalmologic defects. Breeds with merle coat pattern are Shetland Sheepdog, Collie, Border Collie, Australian Shepherd, Cardigan Welsh Corgi, Catahoula Leopard Dog, Dachshund, Great Dane, Bergamasco Sheepdog and Pyrenean Shepherd. The Coat Colour Merle test (H930) tests for the genetic status of the M-locus. The M-locus has three variants (alleles): M (merle, SINE with longer poly-A tail), Mc (cryptic merle, SINE with shorter poly-A tail) and N (non-merle, no SINE insertion. Dogs with cryptic merle (also called phantom or ghost merle), typically display little to no merling and some may be misclassified as non-merles.
Test specific information
This test is performed by VetMedLabor. This test is patented in certain countries. We offer our clients two options for this test because we are not allowed to perform the test in our laboratory.
Firstly, the test can be ordered through a licensee of the patent owner. In this case, the patent owner requires that privacy sensitive information is provided. Per submitted sample a fully filled out form Form ‘Permission providing personal and animal data to patent owner ‘ is required.
As a second option, the test can be forwarded to a partner laboratory in non-patented territory.
Between these two options, a price difference is in place which is caused by the royalties costs on the test. The tests performed by both labs are technical identical.
Since 2015, two brands have been developed. CombiGen®
is mainly directed at veterinarian applications, whereas CombiBreed®
is mainly directed at breeders and/or owners.
Detailed information about Coat Colours and Coat Variation is presented at www.combibreed.com.
Most coat colours and coat types are usually visible directly after birth.
Turn Around Time
The turn-around-time of a test depends to a large extent on the logistics of sample transportation to the laboratory. After receiving the sample at the test location, you can normally expect the result within 10 working days. A longer delivery time applies to tests carried out by a Partner Lab.
Location of disease or trait
Genetic factors influencing coat colours and coat types are usually visible on the outside of an individual. Several factors may be hidden by the external variation.
For this test samples from all breeds are accepted.
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.