Test Detail
Canine multifocal retinopathy (CMR1)
Ocular · Dog
Canine multifocal retinopathy 1 (CMR1) is a hereditary ocular disease caused by a mutation in BEST1. It produces multiple areas of retinal degeneration (raised subretinal lesions, with focal tapetal hyperreflectivity) that develop around 13 weeks of age and progress with age. It is usually of benign course and does not usually cause blindness, but it is an animal model of human bestrophinopathies. The molecular test detects the cmr1 variant and allows it to be differentiated from cmr2 and cmr3.
Incidence
Breeds with CMR1 listed in OMIA:001444-9615: American Bulldog, Australian Shepherd, Boerboel, Bullmastiff, Dogue de Bordeaux, English Bulldog, English Mastiff, Great Pyrenees, Italian Cane Corso and Perro de Presa Canario. The French Bulldog appears in the laboratory's price list, but OMIA:001444-9615 does not list it and there is no publication confirming the cmr1 variant in that breed: limited data, pending confirmation with the laboratory. The Coton de Tulear and the Lapponian dogs correspond to CMR2/CMR3, not to CMR1.
Breeder management
- Do not breed affected animals or carriers with each other (OMIA:001444-9615).
- If a carrier must be used, cross it only with a tested normal homozygote.
- Confirm the status by molecular test before breeding.
- If a carrier must be used, cross it only with a tested normal homozygote.
- Confirm the status by molecular test before breeding.
Specialist notes
Diagnosis by ophthalmoscopy and molecular confirmation. Differentiate from other hereditary retinopathies and from acquired retinal degeneration. It is important to distinguish cmr1 (BEST1 c.73C>T) from cmr2 (Coton de Tulear) and cmr3 (other BEST1 variants), since the test must be variant-specific. Follow-up with OCT/ERG is useful in research animals; in clinical practice examination of the fundus is usually sufficient.
References
1. Guziewicz KE, Zangerl B, Lindauer SJ, et al. Bestrophin gene mutations cause canine multifocal retinopathy: a novel animal model for best disease. Invest Ophthalmol Vis Sci. 2007;48(5):1959-1967. PMID: 17460247.
2. Gornik KR, Pirie CG, et al. Canine multifocal retinopathy caused by a BEST1 mutation in a Boerboel. Vet Ophthalmol. 2014;17(5):368-372. PMID: 23998685.
3. Grahn BH, Philibert H, et al. Multifocal retinopathy of Great Pyrenees dogs. Vet Ophthalmol. 1998;1(4):211-221. PMID: 11397233.
4. OMIA:001444-9615. Multifocal retinopathy 1 in Canis lupus familiaris. https://omia.org/OMIA001444/9615/
5. OMIA:001553-9615. Multifocal retinopathy 2 in Canis lupus familiaris. https://omia.org/OMIA001553/9615/
6. OMIA:001554-9615. Multifocal retinopathy 3 in Canis lupus familiaris. https://omia.org/OMIA001554/9615/
Nota de alcance (2026-09-18): test aplicable a las razas del OMIA:001444-9615 (incluye Bulldog inglés; NO incluye Bulldog francés). En packs solo se incluye donde el gen está validado en la raza del pack: cmck/fn dependen de decisión de laboratorio. Criterio de inclusión en packs: demanda de club para la raza + validación OMIA/publicación.
2. Gornik KR, Pirie CG, et al. Canine multifocal retinopathy caused by a BEST1 mutation in a Boerboel. Vet Ophthalmol. 2014;17(5):368-372. PMID: 23998685.
3. Grahn BH, Philibert H, et al. Multifocal retinopathy of Great Pyrenees dogs. Vet Ophthalmol. 1998;1(4):211-221. PMID: 11397233.
4. OMIA:001444-9615. Multifocal retinopathy 1 in Canis lupus familiaris. https://omia.org/OMIA001444/9615/
5. OMIA:001553-9615. Multifocal retinopathy 2 in Canis lupus familiaris. https://omia.org/OMIA001553/9615/
6. OMIA:001554-9615. Multifocal retinopathy 3 in Canis lupus familiaris. https://omia.org/OMIA001554/9615/
Nota de alcance (2026-09-18): test aplicable a las razas del OMIA:001444-9615 (incluye Bulldog inglés; NO incluye Bulldog francés). En packs solo se incluye donde el gen está validado en la raza del pack: cmck/fn dependen de decisión de laboratorio. Criterio de inclusión en packs: demanda de club para la raza + validación OMIA/publicación.