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HIGH QUALITY DNA
TESTING YOU CAN TRUST
OUR PANELS
The tests in our DNA health testing panels are selected based on the scientific evidence available for disorders in the breed. Our scientists stay up to date with the latest developments and discoveries in the field to ensure that our testing panels are as up-to-date as possible.
DID YOU KNOW?
Our ISO-accredited testing services are relied upon by UK police forces for assessing the suitability of canine recruits for police duties.
TESTIMONIALS
approx. 2 weeks
Typical turnaround
8
Conditions screened
Simple cheek swab
At-home sampling
UK laboratory
Tested in-house
Macular Corneal DystrophyMCD
MCD is an inherited eye disease that causes problems with a dog's sight. In affected dogs, a build up of carbohydrate causes the surface of the eye (the cornea) to become cloudy.
Dogs with MCD usually show signs around four to six years old. Affected dogs will have cloudy eyes that may have grey or white spots on the surface. As their eyes become cloudier, they may have problems seeing and may be more likely to bump into things, walk more slowly or may be more nervous when visiting new places.
How it's inherited
Recessive
What your result means
Clear (N/N): no copies; not expected to develop MCD nor pass it on.
Carrier (N/MCD): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (MCD/MCD): two copies; expected to develop MCD. Discuss with your vet.
Stargardt DiseaseSTGD
Stargardt disease (STGD) is an inherited eye condition that gets worse as a dog gets older. This disease affects the parts of the eye that sense light (the photoreceptors), causing them to deteriorate. As the photoreceptors break down, the dog's eyesight becomes worse in both daylight and dim light.
Affected dogs often develop signs of the disease before they are ten years old. These signs can include loss of vision, dilated pupils, and a reduced response to light. Dogs that are affected by Stargardt disease don't usually go completely blind, but retain some degree of vision.
How it's inherited
Recessive
What your result means
Clear (N/N): no copies; not expected to develop STGD, nor pass it on.
Carrier (N/STGD): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (STGD/STGD): two copies; expected to develop STGD. Discuss with your vet.
Centronuclear MyopathyCNM
Centronuclear Myopathy (CNM) is a reduction in muscle fibres causing muscle weakness, abnormal posture and gait, and exercise intolerance and collapse. Symptoms are variable but dogs are generally weak by five months of age and progression of the disorder ends around one year.
Centronuclear Myopathy is an autosomal recessive condition caused by a mutation in the HACD1 gene.
How it's inherited
Recessive
What your result means
Clear (N/N): no copies; not expected to develop CNM, nor pass it on.
Carrier (N/CNM): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (CNM/CNM): two copies; expected to develop CNM. Discuss with your vet.
Exercise-Induced CollapseEIC
Exercise Induced Collapse (EIC) is a neuromuscular disorder. After strenuous activity affected dogs will display hindlimb weakness and incoordination with usually a return to normal after around 30 minutes.
An autosomal recessive condition caused by a mutation in the DNM1 gene.
How it's inherited
Recessive
What your result means
Clear (N/N): no copies; not expected to develop EIC, nor pass it on.
Carrier (N/EIC): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (EIC/EIC): two copies; expected to develop EIC. Discuss with your vet.
Hereditary Nasal ParakeratosisHNPK
Hereditary Nasal Parakeratosis (HNPK) causes a dry, rough, and crusty nose which can sometimes crack painfully. Affected dogs are otherwise healthy but the must be continually treated to prevent excessive dryness.
An autosomal recessive condition caused by a mutation in the SUV39H2 gene.
Note: Whippets present a different variant so this test is not applicable to Whippets as it is the Retriever type.
How it's inherited
Recessive
What your result means
Clear (N/N): no copies; not expected to develop HPNK, nor pass it on.
Carrier (N/HPNK): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (HPNK/HPNK): two copies; expected to develop HPNK. Discuss with your vet.
Progressive Retinal Atrophy -PRCDPRA-PRCD
Progressive Retinal Atrophy, progressive rod-cone degeneration type (PRA-PRCD), is an inherited eye condition in which the light-sensing cells of the retina gradually break down. It leads to night blindness first, then progressive loss of vision, often ending in blindness. Onset and speed vary. Testing supports breeding choices and early awareness.
Signs to look for
Early night blindness or reluctance in the dark, bumping into things in low light, dilated pupils or a reflective 'shine' to the eyes, progressing to daytime vision loss.
How it's inherited
Recessive — a dog needs two copies of the variant to be affected.
What your result means
Clear (N/N): no copies; not expected to develop PRA-PRCD, nor pass it on.
Carrier (N/PRA): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (PRA/PRA): two copies; expected to develop PRA-PRCD. Discuss with your vet.
Skeletal Dysplasia 2SD2
Skeletal Dysplasia (SD2) causes short legs with a normal body, often slightly shorter in the front than the back legs. Height becomes 6cm smaller on average, though this can be variable due to other factors. Affected dogs are not prone to other health problems and lead a normal life.
An autosomal recessive condition caused by a mutation in the COL11A2 gene.
How it's inherited
Recessive
What your result means
Clear (N/N): no copies; not expected to develop SD2, nor pass it on.
Carrier (N/SD2): one copy. Healthy, but can pass it on. Breeding two carriers risks affected puppies.
Affected (SD2/SD2): two copies; expected to develop SD2. Discuss with your vet.
Degenerative MyelopathyDM
Degenerative Myelopathy (DM) is a progressive disease of the spinal cord that usually appears in older dogs. It gradually weakens the hind limbs, leading to loss of coordination and eventually difficulty walking. It is not painful, but it is progressive. Knowing a dog's status supports breeding decisions and early awareness.
An autosomal recessive condition with variable expression between breeds caused by a mutation in the SOD1 gene.
Signs to look for
Usually from around 8 years old: wobbliness or dragging of the hind paws, loss of coordination in the back legs, worn nails, and gradually progressing hind-limb weakness.
How it's inherited
Recessive with incomplete penetrance — a dog needs two copies to be at risk, but not every at-risk dog develops signs.
What your result means
Clear (N/N): no copies of the variant; not expected to develop this inherited form.
Carrier (N/DM): one copy. Very unlikely to develop DM, but can pass the variant on.
At risk (DM/DM): two copies. At risk of developing DM, though not all at-risk dogs do.
Macular Corneal DystrophyMCD
- Gene
- LOC489707
- Variant
- c.814C>A (p.R272S) missense mutation
- Inheritance
- autosomal recessive
- OMIA
- OMIA002071 9615
Molecular mechanism
Macular corneal dystrophy is an inherited eye disorder caused by a mutation in the CHST6 gene (called LOC489707). In Labrador Retrievers, the causative variant was identified as a missense mutation c.814C\u0026gt;A (p.R272S), with affected dogs being homozygous for the variant, consistent with an autosomal recessive mode of inheritance (Tetas Pont et al., 2016).
The variant affects the normal structure of the cornea, leading to the accumulation of abnormal material within the corneal stroma. Affected Labrador Retrievers typically develop progressive corneal cloudiness and visual impairment between approximately 4.5 and 6 years of age. Clinical signs include diffuse corneal haze and multiple opaque deposits within the cornea, which may increase over time and result in reduced vision (Busse et al., 2019; 2013).
In a study of Labrador Retrievers, the mutant allele frequency was estimated at 0.017, corresponding to an estimated carrier frequency of approximately 3.3% (Tetas Pont et al., 2016).
References
References
Busse, C., Kafarnik, C., Linn-Pearl, R., Volmer, C., Matiasek, K., Premont, J.E., Dulaurent, T., Douet, J.Y., Gilbert, I., Jalomäki, S., Trost, K., Isard, P.F., Boyd, R., Raymond, I. : Phenotype of macular corneal dystrophy in Labrador Retrievers: A multicenter study. Vet Ophthalmol 22:294-304, 2019. Pubmed reference: 30701649. DOI: 10.1111/vop.12596.
Tetas Pont, R., Downs, L., Pettitt, L., Busse, C., Mellersh, C.S. : A carbohydrate sulfotransferase-6 (CHST6) gene mutation is associated with macular corneal dystrophy in Labrador Retrievers. Vet Ophthalmol 19:488-492, 2016. Pubmed reference: 26585178. DOI: 10.1111/vop.12332.
Busse, C., Kafarnik, C., Tetas, R. et al. : Case report: A form of macular corneal dystrophy in a Labrador retriever. Abstract presentation in European College of Veterinary Ophthalmologists , 2013.
Stargardt DiseaseSTGD
- Gene
- ABCA4
- Variant
- ABCA4:c.4176insC (p.Phe1393Leufs*1395)
- Inheritance
- autosomal recessive
- OMIA
- OMIA002179 9615
Molecular mechanism
Startgardt Disease (ABCA4-related Retinal Atrophy), is an inherited retinal degeneration affecting Labrador Retrievers. The condition is inherited as an autosomal recessive trait and is caused by a frameshift insertion, ABCA4:c.4176insC (p.Phe1393Leufs*1395), in exon 28 of the ABCA4 gene. The causative variant was identified by Mäkeläinen et al., (2019) through whole-genome sequencing.
Affected dogs develop a slowly progressive retinal degeneration leading to visual impairment under both daylight and low-light conditions. Clinical signs include dilated pupils, reduced pupillary light responses, retinal changes visible on ophthalmic examination, and gradual deterioration of vision, although some vision is often retained throughout life (Mäkeläinen et al., 2019; Ekesten et al., 2022).
Genetic testing can identify clear, carrier, and affected dogs, enabling informed breeding decisions to prevent affected puppies.
References
Ekesten, B., Mäkeläinen, S., Ellis, S., Kjellström, U., Bergström, T.F. : Abnormal appearance of the area centralis in Labrador Retrievers with an ABCA4 loss-of-function mutation. Transl Vis Sci Technol 11:36, 2022. Pubmed reference: 35201338. DOI: 10.1167/tvst.11.2.36.
Mäkeläinen, S., Gòdia, M., Hellsand, M., Viluma, A., Hahn, D., Makdoumi, K., Zeiss, C.J., Mellersh, C., Ricketts, S.L., Narfström, K., Hallböök, F., Ekesten, B., Andersson, G., Bergström, T.F. : An ABCA4 loss-of-function mutation causes a canine form of Stargardt disease. PLoS Genet 15:e1007873, 2019. Pubmed reference: 30889179. DOI: 10.1371/journal.pgen.1007873.
Centronuclear MyopathyCNM
- Gene
- HACD1
- Variant
- PTPLA*g9459-9460ins236
- Inheritance
- autosomal recessive
- OMIA
- OMIA001374 9615
Molecular mechanism
Centronuclear Myopathy (CNM) is an inherited neuromuscular disorder characterised by progressive skeletal muscle weakness, hypotonia and muscle atrophy, with clinical signs typically developing from approximately one month of age, although onset may occasionally be delayed until six months of age (Walmsley et al., 2017). Disease severity is variable, ranging from reduced exercise tolerance and gait abnormalities to marked muscle atrophy and collapse (McKerrel \u0026amp; Braund, 1987; Blot et al., 2002). Some affected dogs develop oesophageal muscle weakness, resulting in difficulty swallowing and an increased risk of sudden death, while clinical signs may also be exacerbated by exposure to cold temperatures (McKerrel \u0026amp; Braund, 1987).
Centronuclear Myopathy is inherited as an autosomal recessive condition. Pelé et al., (2005) identified a SINE insertion (PTPLA.9459_9460ins236) in exon 2 of the PTPLA (HACD1) gene on canine chromosome 2 (CFA2) as the causative variant. A worldwide survey of 7,426 Labrador Retrievers identified all 80 clinically affected dogs as homozygous for the variant, while none of the 1,172 heterozygous dogs developed disease, supporting its role as the causative mutation (Maurer et al., 2012). The carrier frequency was reported to be particularly high in the UK (19%), highlighting the importance of genetic testing to identify carriers and inform breeding decisions (Maurer et al., 2012).
References
Blot, S., Tiret, L., Devillaire, A.C., Fardeau, M., Dreyfus, P.A. : Phenotypic description of a canine centronuclear myopathy. Journal of Neurological Science 199:S9, 2002.
Maurer, M., Mary, J., Guillaud, L., Fender, M., Pelé, M., Bilzer, T., Olby, N., Penderis, J., Shelton, G.D., Panthier, J.J., Thibaud, J.L., Barthélémy, I., Aubin-Houzelstein, G., Blot, S., Hitte, C., Tiret, L. : Centronuclear myopathy in Labrador retrievers: a recent founder mutation in the PTPLA gene has rapidly disseminated worldwide. PLoS One 7:e46408, 2012. Pubmed reference: 23071563. DOI: 10.1371/journal.pone.0046408.
McKerrell, R.E., Braund, K.G. : Hereditary myopathy in Labrador Retrievers: clinical variations. Journal of Small Animal Practice 28:479–489, 1987.
Walmsley, G.L., Blot, S., Venner, K., Sewry, C., Laporte, J., Blondelle, J., Barthelemy, I., Maurer, M., Blanchard-Gutton, N., Pilot-Storck, F., et al. (2017). Progressive structural defects in canine centronuclear myopathy indicate a role for HACD1 in maintaining skeletal muscle membrane systems. Am. J. Pathol. 187, 441-456. https://doi.org/10.1016/j.ajpath.2016.10.002
Exercise-Induced CollapseEIC
- Gene
- DNM1
- Variant
- c.767G>T; p.Arg256Leu
- Inheritance
- autosomal recessive
- OMIA
- OMIA001466 9615
Molecular mechanism
Exercise-Induced Collapse (EIC) is characterised by transient episodes of muscle weakness and collapse triggered by strenuous exercise in otherwise healthy young dogs. Clinical signs typically develop within 2 minutes of completing 5–15 minutes of intense exercise and include hindlimb weakness, incoordination and an unsteady gait, which may progress to collapse, extensor rigidity, loss of consciousness and, in rare cases, death. Most dogs recover completely within approximately 30 minutes (Taylor et al., 2008; Patterson et al., 2008).
In retriever breeds, EIC is inherited as an autosomal recessive condition. Patterson et al., (2008) identified a missense mutation (c.767G\u0026gt;T; p.Arg256Leu) in exon 6 of the DNM1 gene on canine chromosome 9 (CFA9) as the causative variant. The variant has been reported in Labrador Retrievers, Chesapeake Bay Retrievers and Curly Coated Retrievers, allowing genetic testing to identify affected and carrier dogs. In a Midwestern US population of Labrador Retrievers, the variant was reported at a relatively high frequency, with 37% of dogs identified as carriers and 3% as homozygous affected, highlighting the importance of genetic testing to inform breeding decisions (Patterson et al., 2008). Although Border Collies can exhibit similar clinical signs, no causative variant has yet been identified for this breed; therefore, this genetic test is not applicable to Border Collies (Norton et al., 2021).
References
Norton, E.M., Minor, K.M., Taylor, S.M., McCue, M.E., Mickelson, J.R. : Heritability and genomic architecture of episodic exercise-induced collapse in Border Collies. Genes (Basel) 12:1927, 2021. Pubmed reference: 34946876. DOI: 10.3390/genes12121927.
Patterson, EE., Minor, KM., Tchernatynskaia, AV., Taylor, SM., Shelton, GD., Ekenstedt, KJ., Mickelson, JR. : A canine DNM1 mutation is highly associated with the syndrome of exercise-induced collapse. Nat Genet 40:1235-9, 2008. Pubmed reference: 18806795. DOI: 10.1038/ng.224.
Taylor, SM., Shmon, CL., Shelton, GD., Patterson, EN., Minor, K., Mickelson, JR. : Exercise-induced collapse of Labrador retrievers: survey results and preliminary investigation of heritability. J Am Anim Hosp Assoc 44:295-301, 2008. Pubmed reference: 18981194.
Hereditary Nasal ParakeratosisHNPK
- Gene
- SUV39H2
- Variant
- Labrador c.972T>G; p.Asn324Lys
- Inheritance
- autosomal recessive
- OMIA
- OMIA001373 9615
Molecular mechanism
Hereditary Nasal Parakeratosis (HNPK) is an inherited skin disorder characterised by the development of crusting and fissuring of the nasal planum from a young age. Affected dogs are otherwise healthy, with the condition primarily affecting the nasal epidermis. Histopathological examination reveals marked parakeratotic hyperkeratosis, characterised by retention of nuclei within the stratum corneum and accumulation of proteinaceous fluid within the superficial epidermal layers (Jagannathan et al., 2013).
HNPK is inherited as an autosomal recessive condition (Page et al., 2003). Jagannathan et al., (2013) identified a missense mutation (c.972T\u0026gt;G; p.Asn324Lys) in the SUV39H2 gene on canine chromosome 2 (CFA2) as the causative variant in Labrador Retrievers.
Note: Whippets present a different variant so this test is not applicable to Whippets as it is the Retriever type.
References
Jagannathan, V., Bannoehr, J., Plattet, P., Hauswirth, R., Drögemüller, C., Drögemüller, M., Wiener, D.J., Doherr, M., Owczarek-Lipska, M., Galichet, A., Welle, M.M., Tengvall, K., Bergvall, K., Lohi, H., Rüfenacht, S., Linek, M., Paradis, M., Müller, E.J., Roosje, P., Leeb, T. : A mutation in the SUV39H2 gene in Labrador Retrievers with hereditary nasal parakeratosis (HNPK) provides insights into the epigenetics of keratinocyte differentiation. PLoS Genet 9:e1003848, 2013. Pubmed reference: 24098150. DOI: 10.1371/journal.pgen.1003848.
Page, N., Paradis, M., Lapointe, J.M., Dunstan, R.W. : Hereditary nasal parakeratosis in Labrador Retrievers Veterinary Dermatology 14:103-10, 2003. Pubmed reference: 12662268.
Progressive Retinal Atrophy -PRCDPRA-PRCD
- Gene
- PRCD
- Variant
- c.5G>A (p.Cys2Tyr)
- Inheritance
- autosomal recessive
- OMIA
- OMIA 001298 9615
- Reported frequency
- A single PRCD variant is shared across a large number of breeds, making it one of the most commonly tested PRA forms.
Molecular mechanism
Progressive retinal atrophy (PRA) encompasses a genetically heterogeneous group of inherited retinal degenerative disorders characterised by the progressive loss of photoreceptor function, ultimately resulting in irreversible blindness. Although the clinical presentation is broadly similar across affected breeds, with initial degeneration of rod photoreceptors causing night blindness followed by cone degeneration and progressive loss of daylight vision, numerous genetically distinct forms of PRA have been identified (Miyadera et al., 2012; Mowat et al., 2024). Advances in canine molecular genetics have demonstrated that variants in multiple genes involved in photoreceptor development, maintenance and function can produce clinically similar retinal phenotypes. Consequently, breed-specific genetic testing is required, as different forms of PRA are associated with different causative variants.
PRA-PRCD is an autosomal recessive form of progressive retinal atrophy caused by a missense variant in the PRCD gene. PRCD Zangerl et al., (2006) identified a c.5G\u0026gt;A (p.Cys2Tyr) variant that has been reported across numerous dog breeds. Affected dogs are born with normal vision but gradually develop night blindness, progressing to complete blindness as both rod and cone photoreceptors degenerate. Widespread genetic testing has substantially reduced the frequency of this variant in several breeds, although carriers and affected dogs continue to be identified (Zangerl et al., 2006; Lewis \u0026amp; Mellersh, 2019; Clark et al., 2023).
The expanding number of recognised PRA-associated variants highlights the marked genetic heterogeneity underlying inherited retinal degeneration in dogs. While many of these variants are breed-specific, others are shared across multiple breeds through historical founder events. Genetic testing enables accurate identification of affected and carrier dogs, supporting informed breeding decisions aimed at reducing disease prevalence while preserving genetic diversity. As additional causative variants continue to be identified, molecular testing will remain an important tool for improving the diagnosis, management and long-term control of progressive retinal atrophy in canine populations (Lewis \u0026amp; Mellersh, 2019; Mowat et al., 2024).
References
References
Aguirre, G.D., Lohi, H., Kaukonen, M., Murgiano, L. : Formal commentary. PLoS Genet 16:e1009059, 2020. Pubmed reference: 33151924. DOI: 10.1371/journal.pgen.1009059.
Clark, J.A., Anderson, H., Donner, J., Pearce-Kelling, S., Ekenstedt, K.J. : Global frequency analyses of canine progressive rod-cone degeneration-progressive retinal atrophy and Collie eye anomaly using commercial genetic testing data. Genes (Basel) 14:2093, 2023. Pubmed reference: 38003037. DOI: 10.3390/genes14112093.
Downs, L.M., Wallin-Håkansson, B., Boursnell, M., Marklund, S., Hedhammar, Å., Truvé, K., Hübinette, L., Lindblad-Toh, K., Bergström, T., Mellersh, C.S. : A frameshift mutation in golden retriever dogs with progressive retinal atrophy endorses SLC4A3 as a candidate gene for human retinal degenerations. PLoS One 6:e21452, 2011. Pubmed reference: 21738669. DOI: 10.1371/journal.pone.0021452.
Downs, L.M., Bell, J.S., Freeman, J., Hartley, C., Hayward, L.J., Mellersh, C.S. : Late-onset progressive retinal atrophy in the Gordon and Irish Setter breeds is associated with a frameshift mutation in C2orf71. Anim Genet 44:169-77, 2013. Pubmed reference: 22686255. DOI: 10.1111/j.1365-2052.2012.02379.x.
Downs, L.M., Mellersh, C.S. : An intronic SINE insertion in FAM161A that causes exon-skipping is associated with progressive retinal atrophy in Tibetan Spaniels and Tibetan Terriers. PLoS One 9:e93990, 2014. Pubmed reference: 24705771. DOI: 10.1371/journal.pone.0093990.
Downs, L.M., Wallin-Håkansson, B., Bergström, T., Mellersh, C.S. : A novel mutation in TTC8 is associated with progressive retinal atrophy in the golden retriever. Canine Genet Epidemiol 1:4, 2014. Pubmed reference: 26401321. DOI: 10.1186/2052-6687-1-4.
Goldstein, O., Mezey, JG., Boyko, AR., Gao, C., Wang, W., Bustamante, CD., Anguish, LJ., Jordan, JA., Pearce-Kelling, SE., Aguirre, GD., Acland, GM. : An ADAM9 mutation in canine cone-rod dystrophy 3 establishes homology with human cone-rod dystrophy 9. Mol Vis 16:1549-69, 2010. Pubmed reference: 20806078.
Karlskov-Mortensen, P., Proschowsky, H.F., Gao, F., Fredholm, M. : Identification of the mutation causing progressive retinal atrophy in Old Danish Pointing Dog. Anim Genet 49:237-241, 2018. Pubmed reference: 29624701. DOI: 10.1111/age.12659.
Kaukonen, M., Quintero, I.B., Mukarram, A.K., Hytönen, M.K., Holopainen, S., Wickström, K., Kyöstilä, K., Arumilli, M., Jalomäki, S., Daub, C.O., Kere, J., Lohi, H. : A putative silencer variant in a spontaneous canine model of retinitis pigmentosa. PLoS Genet 16:e1008659, 2020. Pubmed reference: 32150541. DOI: 10.1371/journal.pgen.1008659.
Kropatsch, R., Petrasch-Parwez, E., Seelow, D., Schlichting, A., Gerding, WM., Akkad, DA., Epplen, JT., Dekomien, G. : Generalized progressive retinal atrophy in the Irish Glen of Imaal Terrier is associated with a deletion in the ADAM9 gene. Mol Cell Probes 24:357-63, 2010. Pubmed reference: 20691256. DOI: 10.1016/j.mcp.2010.07.007.
Lewis, T.W., Mellersh, C.S. : Changes in mutation frequency of eight Mendelian inherited disorders in eight pedigree dog populations following introduction of a commercial DNA test. PLoS One 14:e0209864, 2019. Pubmed reference: 30650096. DOI: 10.1371/journal.pone.0209864.
Mellersh, CS., Boursnell, ME., Pettitt, L., Ryder, EJ., Holmes, NG., Grafham, D., Forman, OP., Sampson, J., Barnett, KC., Blanton, S., Binns, MM., Vaudin, M. : Canine RPGRIP1 mutation establishes cone-rod dystrophy in miniature longhaired dachshunds as a homologue of human Leber congenital amaurosis. Genomics 88:293-301, 2006. Pubmed reference: 16806805. DOI: 10.1016/j.ygeno.2006.05.004.
Mowat, F.M., Iwabe, S., Aguirre, G.D., Petersen-Jones, S.M. : Consensus guidelines for nomenclature of companion animal inherited retinal disorders. Vet Ophthalmol 28:663-667, 2024. Pubmed reference: 38334230. DOI: 10.1111/vop.13185.
Miyadera, K., Acland, G.M., Aguirre, G.D. : Genetic and phenotypic variations of inherited retinal diseases in dogs: the power of within- and across-breed studies. Mamm Genome 23:40-61, 2012. Pubmed reference: 22065099. DOI: 10.1007/s00335-011-9361-3.
Murgiano, L., Becker, D., Torjman, D., Niggel, J.K., Milano, A., Cullen, C., Feng, R., Wang, F., Jagannathan, V., Pearce-Kelling, S., Katz, M.L., Leeb, T., Aguirre, G.D. : Complex structural PPT1 variant associated with non-syndromic canine retinal degeneration. G3 (Bethesda) 9:425-437, 2019. Pubmed reference: 30541930. DOI: 10.1534/g3.118.200859.
Petersen-Jones, S.M., Entz, D.D., Sargan, D.R. : CGMP phosphodiesterase-alpha mutation causes progressive retinal atrophy in the Cardigan Welsh corgi dog Investigative Ophthalmology \u0026amp; Visual Science 40:1637-1644, 1999. Pubmed reference: 10393029.
Suber, M.L., Pittler, S.J., Qin, N., Wright, G.C., Holcombe, V., Lee, R.H., Craft, C.M., Lolley, R.N., Baehr, W., Hurwitz, R.L. : Irish Setter Dogs Affected with Rod/Cone Dysplasia Contain a Nonsense Mutation in the Rod cGMP Phosphodiesterase beta- Subunit Gene Proceedings of the National Academy of Sciences of the United States of America 90:3968-3972, 1993. Pubmed reference: 8387203.
Svensson, M., Olsén, L., Winkler, P.A., Petersen-Jones, S.M., Bergström, T., Garncarz, Y., Narfström, K. : Progressive retinal atrophy in the Polski Owczarek Nizinny dog: a clinical and genetic study. Vet Ophthalmol 19:195-205, 2016. Pubmed reference: 26009980. DOI: 10.1111/vop.12284.
Wiik, A.C., Ropstad, E.O., Ekesten, B., Karlstam, L., Wade, C.M., Lingaas, F. : Progressive retinal atrophy in Shetland sheepdog is associated with a mutation in the CNGA1 gene. Anim Genet 46:515-21, 2015. Pubmed reference: 26202106. DOI: 10.1111/age.12323.
Winkler, P.A., Ekenstedt, K.J., Occelli, L.M., Frattaroli, A.V., Bartoe, J.T., Venta, P.J., Petersen-Jones, S.M. : A large animal model for CNGB1 autosomal recessive retinitis pigmentosa. PLoS One 8:e72229, 2013. Pubmed reference: 23977260. DOI: 10.1371/journal.pone.0072229.
Zangerl, B., Goldstein, O., Philp, AR., Lindauer, SJ., Pearce-Kelling, SE., Mullins, RF., Graphodatsky, AS., Ripoll, D., Felix, JS., Stone, EM., Acland, GM., Aguirre, GD. : Identical mutation in a novel retinal gene causes progressive rod-cone degeneration in dogs and retinitis pigmentosa in humans. Genomics 88:551-563, 2006. Pubmed reference: 16938425. DOI: 10.1016/j.ygeno.2006.07.007.
Skeletal Dysplasia 2SD2
- Gene
- COL11A2
- Variant
- COL11A2:c.143G>C
- Inheritance
- autosomal recessive
- OMIA
- OMIA001772 9615
Molecular mechanism
Skeletal Dysplasia 2 (SD2) is an inherited mild form of disproportionate dwarfism in Labrador Retrievers, characterised by shortened limbs with a normal body length and width. Affected dogs have an average reduction in shoulder height of approximately 6 cm (Frischknecht et al., 2013). As shoulder height is influenced by both genetic and environmental factors, affected dogs cannot always be reliably identified by physical appearance alone (Frischknecht et al., 2013).
Skeletal Dysplasia 2 is inherited as a monogenic autosomal recessive condition. Frischknecht et al., (2013) identified a missense mutation (c.143G\u0026gt;C; p.Arg48Pro) in the COL11A2 gene on canine chromosome 12 (CFA12) as the most likely causative variant. The carrier frequency was estimated at approximately 12% in the European Labrador Retriever population at the time of variant discovery, highlighting the value of genetic testing to confirm the diagnosis and inform breeding decisions (Frischknecht et al., 2013).
References
Frischknecht, M., Niehof-Oellers, H., Jagannathan, V., Owczarek-Lipska, M., Drögemüller, C., Dietschi, E., Dolf, G., Tellhelm, B., Lang, J., Tiira, K., Lohi, H., Leeb, T. : A COL11A2 mutation in Labrador retrievers with mild disproportionate dwarfism. PLoS One 8:e60149, 2013. Pubmed reference: 23527306. DOI: 10.1371/journal.pone.0060149.
Degenerative MyelopathyDM
- Gene
- SOD1
- Variant
- c.118G>A (p.Glu40Lys)
- Inheritance
- autosomal recessive
- OMIA
- OMIA 000263 9615
- Reported frequency
- One of the most widespread canine disease variants, reported across very many breeds with varying penetrance.
Molecular mechanism
Degenerative Myelopathy (DM) is a progressive neurodegenerative disease of the spinal cord that typically affects dogs older than 8 years of age. The condition is characterised by progressive muscle atrophy and weakness of the limbs, advancing to tetraparesis (Awano et al., 2009) and eventually respiratory muscle failure (Nardone et al., 2016). DM is inherited as an autosomal recessive condition with variable expression between breeds. Missense mutation (c.118G\u0026gt;A; p.E40K) in exon 2 of the SOD1 gene on canine chromosome 31 (CFA31) was identified as the primary genetic risk factor by Awano et al., (2009). However, some dogs homozygous for the variant remain clinically unaffected, demonstrating incomplete penetrance. The SOD1.118G\u0026gt;A risk allele has been identified in 222 dog breeds. Burnese Mountain Dogs are also susceptible to this version of DM in addition to their breed-specific variant of DM, see DM- BMD variant for further information.
References
Awano, T., Johnson, GS., Wade, CM., Katz, ML., Johnson, GC., Taylor, JF., Perloski, M., Biagi, T., Baranowska, I., Long, S., March, PA., Olby, NJ., Shelton, GD., Khan, S., O\u0026#39;Brien, DP., Lindblad-Toh, K., Coates, JR. : Genome-wide association analysis reveals a SOD1 mutation in canine degenerative myelopathy that resembles amyotrophic lateral sclerosis. Proc Natl Acad Sci U S A 106:2794-9, 2009. Pubmed reference: 19188595. DOI: 10.1073/pnas.0812297106.
Nardone, R., Höller, Y., Taylor, A.C., Lochner, P., Tezzon, F., Golaszewski, S., Brigo, F., Trinka, E. : Canine degenerative myelopathy: a model of human amyotrophic lateral sclerosis. Zoology (Jena) 119:64-73, 2016. Pubmed reference: 26432396. DOI: 10.1016/j.zool.2015.09.003.
Zeng, R., Coates, J.R., Johnson, G.C., Hansen, L., Awano, T., Kolicheski, A., Ivansson, E., Perloski, M., Lindblad-Toh, K., O\u0026#39;Brien, D.P., Guo, J., Katz, M.L., Johnson, G.S. : Breed distribution of SOD1 alleles previously associated with canine degenerative myelopathy. J Vet Intern Med 28:515-21, 2014. Pubmed reference: 24524809. DOI: 10.1111/jvim.12317.
