Multidrug Sensitivity is caused by a deletion in the ABCB1 gene, also known as the multidrug resistance 1 (MDR1) gene, and is characterized by neurotoxicity following the use of certain common drugs. Dogs with two copies of MDR1 will exhibit multidrug sensitivity. Some dogs with 1 copy of MDR1 may also exhibit multidrug sensitivity.
Progressive rod-cone degeneration (PRCD) is an inherited form of late-onset progressive retinal atrophy (PRA) that has been identified in many dog breeds.
Two variants in the Keratin-71 gene are associated with curly hair in dogs. Dogs with these curl variants have curly coats or wavy coats depending on how many copies of the allele they possess.
White spotting patterns that occur in many dog breeds do not have a uniform genetic basis, and the genetics are complex. In piebald/parti/random white spotting, the extent of white pattern expression varies, and markings are often asymmetrical.