PHPT in the Keeshond has an autosomal dominant mode of
inheritance. The test confirms whether a dog is
'negative' for the PHPT gene (clear) or 'positive' for the PHPT
gene (single affected). There is no carrier state in a dominant
mode of inheritance.
If dogs that are positive (single affected) for the PHPT gene
are bred from they will pass a defective gene on to approximately
50% of their offspring if one parent only is positive, or
approximately 75% of the offspring if both are positive. Research
has shown that two positive parents can produce reduced litter
sizes because there are some puppies that do not survive to birth.
Only one positive parent is needed to pass the gene onto some of
their progeny. The disease is known to have 'age dependant
'penetrance'' which means that most or all animals that carry the
gene will go onto develop the disease if they live long enough.
The DNA test does not identify the clinical disease but rather
indicates the presence of the gene. This indicates the genetic
potential to develop the disease later in life. If both sire
and dam are negative (clear) for the defective gene then the
progeny will be hereditarily clear (negative by descent) as they
cannot inherit what their parents did not have.
Test results for this disease are not currently automatically
sent to the Kennel Club for inclusion on its database and therefore
submission of results by the owner is required in order for the
results to be recorded. Please email the Health & Breeding
Services Team for further information.
Tables listing Clears (in PDF format) are available from the
Keeshonds - Clears