Test Detail

Juvenile myoclonic epilepsy of the Rhodesian ridgeback, with myoclonic jerks of juvenile onset and photosensitivity in some animals, phenotypically close to human juvenile myoclonic epilepsy. It is caused by a deletion in DIRAS1 and is inherited in an autosomal recessive manner with complete penetrance.

Affected breed: Rhodesian ridgeback. Limited data on the exact frequency of carriers and cases.

- Test breeders before mating\n- Do not cross two carriers: 25 % of the litter would be affected homozygotes\n- A carrier may be crossed with a clear dog; offspring intended for breeding must be tested\n- Do not breed affected animals\n- Avoid crossing lines with a history of JME and record seizures in the pedigree

Differential diagnosis with other generalized epilepsies and with toxic/metabolic myoclonus. The EEG may show generalized discharges with a photosensitive response. Management with antiepileptic drugs (levetiracetam, valproic acid) and control of light triggers.

1. Wielaender F et al. 2017. Generalized myoclonic epilepsy with photosensitivity in juvenile dogs caused by a defective DIRAS family GTPase 1. Proceedings of the National Academy of Sciences USA. PMID: 28223533
2. Wielaender F et al. 2018. Absence Seizures as a Feature of Juvenile Myoclonic Epilepsy in Rhodesian Ridgeback Dogs. Journal of Veterinary Internal Medicine. PMID: 29194766
3. OMIA:002095-9615. Epilepsy, generalized myoclonic, with photosensitivity. Online Mendelian Inheritance in Animals.