A Causative Mutation in Tac1 Promoter Region Is Associated With Excitability Trait in Belgian Malinois Dogs

Background and aim: the genetic architecture of behavioral traits in dogs allows biologists to obtain unique insights regarding the genetic bases of behavioral diversity. thus dog, showing various behavioral characteristics, is an ideal animal for clarifying the genomic background of behavioral traits. one of the most important behavioral traits in police dogs is trainability and excitability. identification of the genetic background of these traits in dogs could help breeders to earlier select and train pups suitable as police dogs. the results of our previous study showed that the tac1 gene could be a strong candidate associated with behavioral traits in canine dogs. therefore, in this research, we tried to sequence the structure of this gene and evaluation its variations on behavior traits in caine.methods: to achieve this, the behavioral characteristics of a population of 80 belgian malinois were evaluated using a questionnaire that was based on the canine behavioral assessment and research questionnaire (c-barq). then, the total dna of the samples was isolated using the salting-out method. the target regions of tac1 gene was amplified by polymerase chain reaction (pcr) using suitable primers. the sscp analysis was performed on all amplified fragments, separately. consequently, the different patterns of the sscps were sequenced.results: in this study, two single nucleotide polymorphisms (snps) were identified in the candidate gene. glm analysis showed that the c-83 >t mutation was significantly (p < 0.02) associated with the excitability trait in this population. further investigation revealed that c-83 >t mutation located in the canine tac1 putative promoter region and affected p53 related factors binding site.conclusion: the result of this study suggest that the variation in the canine tac1 promoter region could affect canine excitability and trainability by altering tac1 transcriptional activity.