Dr. van Haeringen Laboratorium B.V.

P387 Distichiasis


Distichiasis is an ocular disorder which causes eyelashes to grow through the Meibomian glands of the eyelid. Therefore, a second row of eyelashes is formed, called distichiae.

Distichiae eyelashes differ from normal ones, they can be shorter, thinner, and less pigmented or thick and stiff. This can cause tearing, corneal irritation, keratitis, and corneal erosions or ulcers, which can impact ocular comfort and vision, and may lead to secondary infection. This may even lead to loss of the eye.

Test specific information

This test is based on a genome wide association study. This study described a genetic mutation that is associated with distichiasis in Friesian horses. The inheritance of this mutation is not yet fully understood. A recessive mode of inheritance is proposed, the penetrance of the mutation has yet to be further researched.


Turnaround time

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 disease mainly affects vision, and may result in blindness.

Breed dependence

This DNA test is available for the following breeds: Friesian Horse. Additional information is available in the Frequently Asked Questions (FAQ).

Sample type

For this DNA test we accept the following materials: Blood EDTA, Blood Heparin, Semen, Saliva, Swab. Please contact Dr. Van Haeringen Laboratorium if you wish to submit other material as listed.



The inheritance of this disease is not completely clear.

Severity of Disease


Code P387


€ 57,48 (Incl. 21% VAT)
€ 47,50 (Excl. VAT)