Leonberger: genetic polyneuropathy and the value of DNA screening
A young Leonberger showing gradually worsening hind-leg weakness or a voice that starts to change isn't necessarily dealing with a passing issue: the breed is affected by a hereditary polyneuropathy whose causative mutation has been pinned down with precision. Find all our health pointers in the dog care and grooming section.
What the landmark genetic study shows
A study by Ekenstedt, Becker, Minor and colleagues, published in 2014 in PLOS Genetics, identified a deletion in the ARHGEF10 gene strongly associated with a juvenile-onset polyneuropathy in Leonbergers and Saint Bernards (study on Google Scholar). The authors were able to develop a targeted genetic test that identifies carrier dogs before the first clinical symptoms even appear, a meaningful advance for a disease that used to be hard to anticipate.
What the test changes in practice
- A simple saliva-based screen, available from a very young age, that reveals a puppy's genetic status well before any clinical sign shows up.
- A valuable tool for breeders, who can avoid pairing two carriers and so gradually reduce how common the mutation is within the breed.
- Targeted veterinary follow-up for dogs identified as carriers, with close attention paid to gait and voice from the first few months.
Spotting the early signs
A gait that gradually changes, a voice that becomes noticeably raspier, or unusual fatigue on exertion in a young Leonberger should prompt a swift neurological consultation. That specialist follow-up comes with a cost that a dog health insurance plan can help cover. Find the full breed profile on the Leonberger page and browse all our guides on the dog hub.
Frequently asked questions
Is the genetic test reliable for screening the disease?
It identifies the mutation linked to the disease with good reliability, making it a valuable tool even before any symptoms appear.
Will a carrier Leonberger definitely develop the disease?
The link between the mutation and the disease is strong, but only regular veterinary follow-up can confirm how the dog's condition actually develops.
At what age do the first symptoms usually appear?
The juvenile-onset form described in the study most often shows up during the first few months of life, which is why early screening matters.
This guide is part of Planète Pets’s Dogs universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.