Protein expression and genetic variability of canine Can f 1 in golden and Labrador retriever service dogs. Issue 1 (December 2016) - Breitenbuecher, Christina
Abstract Background Valued for trainability in diverse tasks, dogs are the primary service animal used to assist individuals with disabilities. Despite their utility, many people in need of service dogs are sensitive to the primary dog allergen, Can f 1, encoded by theLipocalin 1 gene (LCN1 ). Several organizations specifically breed service dogs to meet special needs and would like to reduce allergenic potential if possible. In this study, we evaluated the expression of Can f 1 protein and the inherent variability ofLCN1 in two breeds used extensively as service dogs. Saliva samples from equal numbers of male and female Labrador retrievers (n = 12), golden retrievers (n = 12), and Labrador-golden crosses (n = 12) were collected 1 h after the morning meal. Can f 1 protein concentrations in the saliva were measured by ELISA, and theLCN1 5′ and 3′ UTRs and exons sequenced. Results There was no sex effect (p > 0.2) nor time-of-day effect; however, Can f 1 protein levels varied by breed with Labrador retrievers being lower than golden retrievers (3.18 ± 0.51 and 5.35 ± 0.52 μg/ml, respectively, p < 0.0075), and the Labrador-golden crosses having intermediate levels (3.77 ± 0.48 μg/ml). Although several novel SNPs were identified inLCN1, there were no significant breed-specific sequence differences in the gene and no association ofLCN1 genotypes with Can f 1 expression. Conclusions As service dogs, Labrador retrievers likely have lower allergenic potential and, though there were no DNA sequence differences identified, classical genetic selection on the estimated breeding values associated with salivary Can f 1 expression may further reduce that potential.