19.2 Results: Test results for all genetic disorders will only be
accepted from testing facilities deemed appropriate by the
Association.
19.3 HYPP: Hyperkalaemic Periodic Paralysis.
a) HYPP is an Autosomal Dominant Genetic Disorder,
being a muscular disease caused by a hereditary
genetic disorder that leads to uncontrolled muscle
twitching or profound muscle weakness and in severe
cases may lead to collapse and/or death. According
to research this condition exists in certain
descendants of the stallion “Impressive” AmQHA
#0767248;
b) Horses applying for registration that have lineage to
“Impressive” will be tested for HYPP, except where
both parents have been tested for HYPP with a
negative result on file with the Association, then the
horse applying for registration will not be required to
be tested for HYPP;
c) Horses that return a positive (homozygous/afflicted)
result to HYPP will not be accepted for registration or
recording;
d) Horses that return a positive (heterozygous/carrier)
result to HYPP will be considered for registration with
the Association if gelded or spayed;
Note: Chem ical alternatives to surgical spaying will not
be accepted by the Association;
Exception: Foundation Mares and Foundation Stallions
will not be accepted unless they return a negative result
to HYPP.
e) Horses that return a negative result to HYPP will be
considered for registration;
f) Any horse applying for registration, whose pedigree
does not contain the „Impressive” lineage will not be
required to be tested for HYPP;
Exception: All ASH registered horses applying for
Foundation Recording must complete a HYPP genetic
test and return a negative result to be considered for
recording with the Association;
g) Any registered horse may be required to be tested for
HYPP using the official procedure at the Association‟s
discretion;
h) Horses tested for HYPP will have their registration
papers marked with the test result.
19.4 HERDA/OLWS
a) HERDA (Hereditary Equine Regional Dermal Asthenia)
is an Autosomal Recessive Genetic Disorder.
HERDA is a devastating disease that causes the skin to
lift and peel away. The condition, which renders a horse
unable to wear a saddle or harness, is known by two
names: Hyperelastosis Cutis and Hereditary Equine
Regional Dermal Asthenia. The reported age of onset
ranges from birth to four (4) years old. According to
research this condition exists in certain descendants of
the mare “Miss Taylor” AmQHA #0002636 and stallion
Poco Bueno” AmQHA #0003044;
b) OLWS – Overo Lethal White Syndrome is an
Autosomal Recessive Genetic Disorder in which the
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