HERDA Hereditary Equine Regional Dermal Asthenia

Sample

• 30 to 40 - hair roots - envelope

• 5 mL - blood - K3 EDTA tube

Turnaround time

• 2 to 5  working days

Why test?

• This DNA test helps breeders to identify horses that carrying the HERDA recessive mutation. Informed choices can be made for breeding selections, and prevent the born of affected foals.

Results description

 The DNA test verifies the presence of the recessive HERDA gene and presents results as one of the following:

• N/ - Negative for HERDA. Absence of the defective gene responsible for HERDA.
• N/HERDA - Carrier - Positive heterozygous for HERDA. Presence of one copy of the allele responsible for HERDA.  The horse is a carrier for HERDA and can pass on a copy of HERDA allele to their progeny when bred.
• HERDA/ - Positive Homozygous for HERDA. Presence of two copies of the allele responsible for HERDA.  The horse is affected by  HERDA disorder and can pass the HERDA allele to 100% of their progeny when bred.

Additional information

Hereditary equine regional dermal asthenia (HERDA) is a genetic skin disease predominantly found in the American Quarter Horse. Within the breed, the disease is prevalent in particular lines of cutting horses.

HERDA is characterised by hyper-extensible skin, scarring, and severe lesions along the back of affected horses. Affected foals rarely show symptoms at birth. The condition typically occurs by the age of two, most notably when the horse is first being broke to saddle.

There is no cure, and the majority of diagnosed horses are euthanised because they are unable to be ridden and are inappropriate for future breeding. HERDA has an autosomal recessive mode of inheritance and affects stallions and mares in equal proportions.