JLPP, must all dogs be tested ... also offspring from "clear" parent dogs ?

One of our IFR Member Clubs asked the IFR-Board for an advise about the following : if both parent dogs are found to be free of the defective JLPP-gene, may their offspring then automatically be understood to be free too and therefore be exempt from DNA-testing before being used for breeding ?


The IFR-Board is not mandated or empowered to issue regulations.   It can check if existent regulations are compliant with the constitutional conditions for IFR-Membership and/or with the conditions that the Meeting of Delegates would impose to the Federation’s members but it cannot decide itself on such conditions.

Nevertheless, in the context of the IFR-Constitution that empowers the Board to do all within its means to help realise the goals of the Federation, incl. the preservation of the physical and genetic health of the breed, the Board advises as follows.

We will not go into detail about this disease itself, nor about its Mendelian inheritance.   For those interested, we refer to the IFR-publication : "A layman's walk through basic canine genetics.  Genetic diseases and the correlation with a reduced genetic diversity of the breed" that is published on the IFR-website. (1)

JLPP is an autosome recessive genetic disease with a progressive nature that affects the nervous system.   It is caused by a recessive gene of which the presence (or absence) can be established by a simple DNA-test.

The FCI has since long introduced guidelines on how to cope with such genetic diseases and strongly advises to examine all breeding dogs on the presence of inherited diseases by using DNA-tests :

“Results from DNA tests for inherited diseases should be used to avoid breeding diseased dogs, not necessarily to eradicate the disease.

Dogs shown to be carriers (heterozygote) for a recessive inherited disease should only be bred to a dog that is proven not to carry the allele for the same disease.” (2)

This guideline by the FCI is based on scientific research and should be respected by all : if the existence of inherited diseases is established in a breed, then DNA-tests, if available, should be used to avoid breeding diseased dogs. (3)

The results of such a test must lead to the following breeding decisions :

  • Suffering dogs (in the hypothesis that they live long enough to reach breeding age) may not be used for breeding and most certainly not be combined.   They carry only the defective gene and will necessarily pass it to their offspring and will cause suffering dogs.   
  • The combination of dogs that do not carry the defective gene (= “clear dogs”) is of course allowed : if dogs do not carry the defective gene, they cannot pass it to their offspring.  Their pups will be “clear” too or in other words, the pups will not be carriers, cannot not pass the defective gene to their offspring and will not develop the disease.
  • The combination of carriers is to be forbidden as the law of probability wants that 25 % of the offspring will suffer the disease, 50 % will be carriers and only 25 % will be clear.    We may not breed with combinations that will lead to diseased dogs. 
  • The combination of a carrier with a “clear dog” is allowed.(2)   Probability wants that 50 % of the pups will be “clear” and 50 % will be carriers but as the gene is recessive and not dominant, these carriers will not develop the disease.

The answer on the question if the offspring of parent dogs that are both free of the defective JLPP-gene are necessarily also free and can be exempt from DNA-testing for this defective gene, therefore seems to be very easy : if both parents are free of the defective gene, then the pups will also be free of it and then it seems senseless to subject them to a test before using them as breeding dogs.

However … !!!    Hard and cold reality has proven – not for the first and probably not for the last time - that some dogs still develop JLPP and/or are established to be carriers while both their parents were tested and officially declared to be “clear”.

If both parents would indeed be free from the defective gene, then this would of course be totally impossible !

The fact that these pups develop the disease and/or prove to be carriers, can therefore only be explained by faulty or false test-results.

Such faulty results can be caused by mistakes made by veterinarians or laboratories (e.g. faulty labelling or handling of DNA-samples or mistakes in the reading / interpretation / sending out of results) but also because of fraud !

Whatever the reason, it can lead to an illness and suffering that can and must be avoided  and - especially if one of the parent dogs is a so called “matator-dog” - this may even have an important negative impact on the health of a large part of a breed population.(4)   

A difficult and delicate investigation will then be needed to identify both the dog that is “responsible” and it’s offspring (= potential breeding dogs) that may unknowingly already be affected … but of course by then, serious harm will already be done.

It is therefore the opinion of the IFR-Board that it is in the interest of the breed that the “FCI International Breeding Strategies” should be followed, meaning that all dogs should be tested on the presence of the defective JLPP-gene before being used for breeding, including all dogs whose parents were officially declared to be free of the defective gene.

This will prevent or limit fraud and/or the negative implications of material errors or fraud and will have the benefit of simplicity and clarity in breeding regulations.

A similar statement was also published in 2017 in the ADRK Magazine by Prof. P. Friedrich and is attached to the present document. (5)

As stated above : this is an advice, not a binding rule or regulation … but if we agree that safeguarding the physical and genetic health of our dogs is in the interest of the breed, then ignoring the FCI-strategies for breeding and/or ignoring the fact that those strategies can be undermined by mistakes or fraud, is just not an option !

Once again : facta … non verba !

On behalf of the IFR-Board,

Hasselt, 02 November 2021.

D. Vandecasteele.


(1) The booklet explains basic genetics in an easy to understand manner, goes into some of the genetic diseases that exist in the Rottweiler-breed and explains how the prevalence rate of these diseases is influenced by in- and linebreeding.   The booklet holds a strong warning against the ever more reduced genetic diversity of our breed.   The booklet is available in PDF-format in English and in Spanish.  A printed version is available in English. The following link leads to the text in an online format :

(2) “FCI International Breeding Strategies”, published on

(3) In the before mentioned booklet, the question was raised if we should test for all diseases.  The answer was negative as this would lead to a too limited genetic pool.  There may however be no discussion on the necessity to test for genes that are responsible for life-threatening or life-shortening diseases or diseases that cause serious pain or reduce essential functionality or quality of life.     This is undoubtably the case for JLPP.

(4) The “Matador-effect” : when dogs are for some reason very popular as breeding dogs and produce a high number of offspring.   These dogs do not only transfer the wanted characteristics but they also lead to more homozygotes carrying recessive alleles that cause diseases and unwanted traits.

(5) Qualitätssicherung bei der Fortschreitenden Bekämpfung der Juvenilen Laryngealen Paralyse und Polyneuropathie (jlpp)