Test Detail

Multi-disease genetic panel for the Dachshund grouping four molecular tests: progressive retinal atrophy cord1-PRA (RPGRIP1), progressive retinal atrophy crd-PRA (PDE6B), osteogenesis imperfecta (SERPINH1) and neuronal ceroid lipofuscinosis type 2 (NCL2, TPP1). It combines ocular, skeletal and neurodegenerative conditions. The panel is complementary to ocular and orthopaedic examination in breeding selection.

Dachshund (all coat varieties). cord1-PRA is one of the most frequent PRAs in the breed. OI has a low frequency. NCL2 is rare. Exact frequencies by variety are not reliably published (limited data).

- cord1-PRA: early-onset visual loss (cones)
- crd-PRA: progressive blindness of variable onset
- OI: recurrent fractures due to bone fragility
- NCL2: ataxia, blindness and progressive neurodegeneration

Each condition in the panel was characterized independently. cord1-PRA was associated with the 44 bp insertion in RPGRIP1 in the long-haired miniature Dachshund (Mellersh 2006). crd-PRA was associated with PDE6B in the wire-haired Dachshund. Osteogenesis imperfecta was associated with SERPINH1 c.977C>T (Drögemüller 2009). NCL2 was associated with TPP1 (Awano 2006).

- Genotype breeding animals before mating (four tests in a single sample)
- For cord1-PRA and crd-PRA: do not mate two carriers; carrier×clear is safe if tested; complement with annual ophthalmological examination (ECVO)
- For OI: do not mate two carriers; homozygotes have recurrent fractures
- For NCL2: do not mate two carriers; homozygotes develop ataxia and progressive blindness
- After a confirmed case, do not repeat the parental mating and inform the buyer of the status

cord1-PRA must be distinguished from other PRAs of the Dachshund (crd-PRA, etc.). The definitive diagnosis of each PRA is the molecular test. OI is diagnosed by radiography (multiple fractures, fracture calluses) and molecular test; differentiate from trauma. NCL2 is suspected from juvenile ataxia and confirmed by molecular test. No curative treatment for any of the four.

1. Mellersh CS et al. 2006, RPGRIP1 y cord1-PRA en Teckel (PMID 16806805)
2. Downs LM et al. 2013, C2orf71 y PRA de inicio tardío (rcd4) en Gordon/Irish Setter (PMID 22686255)
3. Drögemüller C et al. 2009, SERPINH1 y osteogénesis imperfecta en Teckel (PMID 19629171)
4. Awano T et al. 2006, mutación con cambio de marco en TPP1 (ortólogo de CLN2 humano) en un Teckel juvenil con NCL (PMID 16621647)