Laboklin has been offering a DS test for Rhodesian Ridgebacks since March 2025. What does this mean for breeding?
Information about the Dermoid Sinus and the test itself can be found on the Laboklin website:
www.laboklin.de
General information
The genetic test itself only assesses the risk factor, not whether the dog has DS or not.
The test categorises dogs into eight possible genotypes: AAGG, ATGG, TTGG, AACG, AACC, ATCG, TTCG, ATCC, TTCC.
These eight genotypes are categorised into five risk groups: very minimal risk, very low-low risk, moderate risk, higher risk, very high risk.
Important: These risk groups refer to the respective dog and not to its offspring!
On the one hand, this risk assessment for the dog in question is helpful because it can be used to guide breeding. However, it is also not very meaningful - we know exactly whether this dog has a dermoid sinus or not. This is because the dermoid sinus is usually tested when the litter is accepted and the dog is also tested for DS at the latest when it is approved for breeding (in Switzerland).
What does this mean for Rhodesian Ridgeback breeding?
Laboklin states that matings resulting in the TTCC variant should be avoided. According to the DZRR (
news item Dermoid Sinus Genetic Test), 83% of TTCC dogs have a dermoid sinus.
The risk assessment should therefore be treated with caution because Rhodesian Ridgebacks with the result ATCG, for example, belong to the second lowest level - but mating with the corresponding partner can result in TTCC dogs!
At the same time a Rhodesian Ridgeback with the result TTGG, which has a higher risk for DS than ATCG, cannot sire a TTCC, no matter with which partner.
So don't rest on the laurels of a good result of your breeding dog (lowest two risk groups), but check carefully!
Simply put: If the result of your Rhodesian Ridgeback contains a T and a C, you should pay attention to the choice of breeding partner!
Tia has the ATCG result and would therefore fall into the group with "breeding control". In our A-litter, only she was tested, but the male dog was not - the test was very new on the market at that time and the experience has not yet been consolidated.
Since I was interested, I calculated the probability of dermoid sinus in my puppies.
If I had bred Tia (ATCG) to a Rhodesian Ridgeback with the same results (ATCG), 27.5% of the puppies would have a DS - so one in four! We had no DS in the A litter!
I only followed the results of the tests posted on Facebook. Of course, this does not give an accurate picture! I have not yet found exact figures on which risk group is present and how often.
However, the ATCG risk group does not appear to be rare. So a mating of ATCG + ATCG should not be too rare.
Frequency of dermoid sinus in breeding
I myself only have the figures from the litter statistics in Switzerland. According to statements, however, the situation is similar in Germany.
In Switzerland, we have had a dermoid sinus rate in puppies (RRCS breedings) of 2-3% of puppies over the last 10-15 years. With around 120 puppies born each year, this means that 3-4 puppies are affected each year.
Official statistics on dermoid sinus speak of much higher numbers. With regard to FCI breeding in Switzerland, I cannot confirm this. Of course, I can only speak to a limited extent about other countries and/or non-FCI breeders.
My conclusion
With a current probability of dermoid sinus in breeding of 2-3%, dermoid sinus is not THE problem of our breed. Even if discussions about torture breeding like to dwell on it.
The dermoid sinus is operated on at puppy age and the Rhodesian Ridgeback then lives a normal life. Rhodesian Ridgebacks that have/had a DS are not used for breeding!
If DS occurs regularly in a line, it is up to the breeder to decide what measures to take.
Assuming these 2-3% of puppies with DS, a majority of Rhodesian Ridgebacks should belong to the risk groups AAGG / AACG / AACC / ATGG / TTGG.
I think it is still too early to give mature feedback on the Dermoid Sinus Test and its handling. It is certainly good that such a test has been developed.
However, it does not save you a look at the individual lines and ancestors when choosing a mating partner.
And very important - as with all genetic aspects: It is urgently necessary to also keep ‘carriers’ in the breeding programme. Only if we keep the carriers in the breeding programme can we guarantee genetic diversity.
In the DS test, I count as so-called ‘carriers’ those dogs with the risk assessment ATCG, TTCG, ATCC, TTCC - i.e. those that would receive ‘breeding control’ according to the recommendation.
