Juvenile Renal Dysplasia (JRD) is NOT a complicated disease (kidney disease), it is quite simple to understand and now with the JRD DNA Test, it is relatively simple to control and possibly eradicate in breeds that are not saturated with it.

JRD damages kidneys’ to varying degrees of severity, those with low level damage survive, those with high level damage die, thankfully deaths are apparently a minority in GSD. (deaths in the womb and still born may be a more serious concern))

1) Matings of JRD Clear to JRD Clear - will always produce JRD CLEAR offspring. No need to test offspring.

2) Matings of JRD Carrier (single) to JRD Clear - could produce some JRD clear (test & choose  from the clear for breeding)

3) Mating of JRD Carrier (single) to JRD Carrier (single) could produce  some JRD clear, some JRD carriers and some JRD homozygote’s (double) - test & choose from the clear for breeding. If no clear choose from the carriers (single) and follow '2' above process when breeding from the carrier.

4) Mating JRD Homozygote (double)  to JRD Clear - will produce ALL JRD carriers (single) - no need to test, select one and follow '2' above process when breeding from the carrier.

5) Mating JRD Homozygote (double) to a JRD Carrier (single) - could produce JRD Carriers (single) and JRD Homozygote (double) - test and choose from the JRD Carriers (single) and then follow '2' above when breeding from it.

6) Mating JRD Homozygote (double) to JRD Homozygote (double) - will always produce JRD Homozygote (double) - such a mating should NOT be done.

You cannot currently treat Hip Dysplasia and many other diseases this way and control and possibly eradicate them from GSD. 

This is the value of DNA Tests, with some diseases, like JRD; it will be possible to control and eradicate some of them by DNA Testing and breeding practices.

Currently, with the apparent low level of JRD Testing in our GSD breed, stud dogs that are not JRD tested may be used by kennels that are mating JRD Tested (Clear) females. The approach I will have when I do this, as when I use a German untested stud dog, will be to place a breeding restriction on the whole litter when I register them, which will be removed when they are JRD tested clear by owners who may wish to breed from them (including those I retain). Or I may have ALL the puppies JRD tested myself (currently a bit expensive). A GSD Breed Council scheme which could BULK buy the JRD tests, and make all the participants JRD results PUBLIC, could make the JRD Tests much cheaper, possibly up to 40% cheaper.