Breed distribution of the nt230(del4) MDR1 mutation in dogs.

A 4-bp deletion mutation associated with multiple drug sensitivity exists in the canine multidrug resistance (MDR1) gene. This mutation has been detected in more than 10 purebred dog breeds as well as in mixed breed dogs. To evaluate the breed distribution of this mutation in Germany, 7378 dogs were screened, including 6999 purebred and 379 mixed breed dogs.

Detection of the nt230[del4] MDR1 mutation in dogs by a fluorogenic 5' nuclease TaqMan allelic discrimination method.

For detection of the nt230[del4] MDR1 mutation, a 4-bp deletion in the canine MDR1 (ABCB1) gene, a TaqMan allelic discrimination assay was designed that allows for MDR1 genotyping without post-PCR processing. Directly after completion of the PCR amplification, the MDR1 genotype can be assigned based on selective fluorescence measurement. For primer selection the locus of a potential 265A>G single nucleotide polymorphism was omitted; this locus is covered by the oligonucleotide PCR primers from most of the hitherto established MDR1 genotyping methods.