What is the value of Genetic testing?
Genetic testing for hereditary diseases is done to determine if an animal is going to develop a disease, or if it is a carrier (Prognostic Testing and Pre-breeding Testing). It can also be done on a sick animal to confirm or exclude a veterinary diagnosis (Diagnostic Testing).
With the help of prognostic tests, disease status can be determined before any clinical symptoms are observed.
Depending upon the disease, early knowledge of disease status may allow pre-symptomatic treatment. Prognostic tests can also predict phenotypes such as coat color and other physical traits.
Prognostic tests allow horse buyers to confirm an animal’s health status for specific diseases prior to purchase. It is also useful to determine if a horse has or carries a desired trait that is not obvious by visual inspection.
Pre-breeding testing is a type of prognostic testing.
Responsible breeders wish to avoid producing foals affected by genetic diseases, and the most effective way to do this is using genetic testing. Both potential parents should be tested to determine if they are affected by, or carriers for, a disease of concern in the breed. Some dominant diseases do not become apparent until after the normal breeding age of the horse. In the case of recessive diseases, carriers are clinically normal but can produce affected foals.
If an animal is ill, diagnostic genetic testing allows veterinarians to confirm or disprove their hypothesis of the cause of the symptoms. This knowledge can guide treatment decisions and allow informed decisions to be made regarding animal care and medical procedures.