So far, the term brindle in horses has been used for similar phenotypes in different breeds. A recent study, conducted with descendants of a single Quarter Horse mare, provided the first qualitative characterization of a distinct brindle phenotype, called “brindle 1” (BR1), together with the most probable causative mutation. It was identified in the MBTPS2 gene and is inherited as a monogenic X-chromosomal semidominant trait. The typical BR1 phenotype with irregular vertical stripes along the neck, back, hindquarters and upper legs is only present in heterozygous females. Females homozygous for the mutation and males carrying a mutated X-chromosome do not show stripes. Their main features are sparse manes and tails.
Test specific information
Symptoms will develop at a young age. Within a few hours to a maximum of several weeks after birth, the characteristics that go with these genetic effects will become visible.
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
This disease is present in the entire body, but causes main effects in the internal organs such as stomach, intestinal tract, liver and / or kidneys. In a number of cases, the disease affects one major internal organ.
This DNA test is available for the following breeds: American Quarter, American Paint Horse. Additional information is available in the Frequently Asked Questions (FAQ).
For this DNA test we accept the following materials: Blood EDTA, Blood Heparin, Semen, Tissue, Hair. Please contact Dr. Van Haeringen Laboratorium if you wish to submit other material as listed.
The following results are possible for a female: the mode of inheritance is based on recessive or dominant patterns.
The following results are possible for a male:
- A male animal has the sex chromosome Y and a healthy allel. When used in breeding, this animal will not become affected by the disease, nor will the disease be inherited to the next generation.
- A male animal has the sex chromosome Y and a disease allel. When used in breeding, this animal will become affected by the disease. Also, male offspring will receive the Y-chromosome, whereas female offspring will receive the disease allele.
The disease is inherited in an X-chromosomal manner. This means, that female individuals can be free (homozygous normal), affected (homozygous affected) or carrier (heterozygous).
Male individuals carry only one copy of the X-chromosome, which results in the effect that male carriers will also be affected.
Female carriers may spread the disease in a population without showing symptoms themselves. Because of this, it is extremely important to identify carriers correctly to prevent spreading of a disease.
Severity of Disease