TDK conference 2019

In the last two decades Hungarian dog breeds have been paid a particular attention to by both veterinarians and dog breeders. Because of the small number of individuals within each species, there has been a growing need for gene conservation. The boom in breeding entails making it better but it requires a thorough knowledge of breeds and the assessment of accidental genetic heredities. Considering this our research intends to examine the deletion of MRD1-gene in Hungarian dog breeds.

The MDR1-gene encodes P-glycoprotein, which is a functional protein expressed in biological barriers, such as brain capillary endothelia. This protein plays an important role in eliminating drugs and metabolites from the central nervous system which might cause toxicosis. If the MDR1-gene contains a 4-base pair mutation, the expressed protein will not function. In these cases, certain groups of active substances can cause symptoms of nervous system disorder even in therapeutic doses, which might be fatal. The groups of harmful substances include macrocyclic lactones, some antineoplastic agents, opioids and cyclosporine.

Our research covers five of the nine Hungarian dog breeds. We have examined 75 animals, including 43 Hungarian vizslas (also wire- and shorthaired), 14 Hungarian greyhounds, 14 mudis and 4 pulis. We have also interpreted earlier MDR1 genetic results of 6 mudis, made by another laboratory.

During our laboratory work, to achieve the isolation of the genomic DNA from the collected blood samples, we used silica gel membrane column method. The MDR1 mutation was determined by modified allele-specific, real-time PCR based genotyping method. Based on our own analyses and tests done in an outside laboratory we found all individuals of the four breeds mutation-free, that is, we did not find either homozygous or heterozygous genotype for the mutation.

Based on the above findings the dog breeds examined are not affected by the deletion of MDR1-gene, thus they can be treated by drugs which are the substrates of P-glycoprotein, furthermore the given genetic heredity needs no attention when breeding them.