Test Detail
Leonberger polyneuropathy type 2 (LPN2)
Neurological · Dog
Molecular test for Leonberger polyneuropathy type 2 (LPN2), a peripheral neuropathy of adult onset and slower progression than LPN1, which produces limb weakness, muscle atrophy and, in some cases, laryngeal involvement. It affects the peripheral nervous system and compromises exercise and quality of life. The test reports clear/carrier/affected status for the corresponding variant.
Incidence
Applicable breed: Leonberger. The frequency of the variant has been described as moderate in some breeding populations (Nordic and North American series); figures for the Spanish population are limited and should be verified in the specific literature.
Breeder management
- Genotype breeding animals before mating\n- Due to dominant inheritance: an animal with the variant (heterozygous or homozygous) can transmit it to the offspring; mating two animals with the variant is inadvisable\n- An affected animal must not be bred; a carrier of the variant should preferably be mated to a clear animal\n- Given the incomplete penetrance, also assess the clinical phenotype (history in the maternal/paternal line)\n- After a confirmed clinical case, do not repeat the parental mating and communicate the status to the buyer
Specialist notes
LPN2 is a differential diagnosis with LPN1 (ARHGEF10 gene, autosomal recessive, juvenile onset and severe; OMIA:001917-9615) and with LPPN3 (CNTNAP1; OMIA:002301-9615) in the Leonberger. Electromyography and nerve conduction studies guide the diagnosis. The incomplete penetrance means that one should not overdiagnose from DNA: an animal with the variant and without clinical signs should be followed with periodic neurological examination. Rule out acquired causes (toxic, endocrine) before attributing the condition to LPN2.
References
1. Becker D et al. 2017. A GJA9 frameshift variant is associated with polyneuropathy in Leonberger dogs. BMC Genomics. PMID: 28841859
2. Ekenstedt KJ et al. 2014. An ARHGEF10 deletion is highly associated with a juvenile-onset inherited polyneuropathy in Leonberger and Saint Bernard dogs (LPN1). PLoS Genet. PMID: 25275565
3. Granger N. 2011. Canine inherited motor and sensory neuropathies: an updated classification in 22 breeds and comparison to Charcot-Marie-Tooth disease. Vet J. PMID: 20638305
4. OMIA:002119-9615 / OMIA:001917-9615.
2. Ekenstedt KJ et al. 2014. An ARHGEF10 deletion is highly associated with a juvenile-onset inherited polyneuropathy in Leonberger and Saint Bernard dogs (LPN1). PLoS Genet. PMID: 25275565
3. Granger N. 2011. Canine inherited motor and sensory neuropathies: an updated classification in 22 breeds and comparison to Charcot-Marie-Tooth disease. Vet J. PMID: 20638305
4. OMIA:002119-9615 / OMIA:001917-9615.