Various genotyping methods for testing multidrug resistance (MDR) in the Hungarian dog population of British herding breeds

Abstract

The multidrug resistant gene 1 (MDR1 or ABCB1) codes for an adenosine triphosphate (ATP) driven P-glycoprotein functions as an efflux pump to extrude unrelated toxic compounds from inside a cell out into the capillary blood stream. A 4 base pair deletion at the nucleotide position 230 results in a severely truncated, nonfunctional P-glycoprotein. The ABCB1-1Δ polymorphism (previously nt230(4del) MDR1 gene defect) is known so far in 13 dog breeds: Collie, Australian Shepherd, Miniature Australian Shepherd. Shetland Sheepdog, Old English Sheepdog, Border Collie, Longhaired Whippet, McNab, Silken Windhound, Wäller, German Shepherd and White Swiss Shepherd. In dogs affected by the hereditary ABCB1-1Δ gene deletion severe neurotoxic phenomena after treatment with P-glycoprotein substances can lead to severe clinical symptoms up to lethal consequences. The aim of our study was to measure the ABCB1-1Δ gene defect in British herding breeds in Hungary and to test the existing genotyping screening methods from the point of view of effectiveness and reliability.