CMR3 (Canine Multifocal Retinopathy)

Canine Multifocal Retinopathy (CMR) is an eye disorder characterised by multiple areas of retinal degenerationm, potentially causing a loss of central vision. This variant of the disorder, CMR3, occurs specifically in the Lapponian Herder and Finnish Lapphund, and is caused by a recessive mutation to the gene BEST1.

On veterinary clincal examination, signs of CMR include multiple tan-pink subretinal patches (“blisters”) in both the tapetal and the non-tapetal fundus along with focal areas of tapetal hyper-reflectivity. The disorder does not typically lead to blindness.