title: Differences in behavior and activity associated with a poly(a) expansion in the dopamine transporter in Belgian Malinois.
abstract: In Belgian Malinois dogs, a 38-base pair variable number tandem repeat in the dopamine transporter gene (SLC6A3) is associated with behavior changes in Malinois. By additional sequencing in SLC6A3, we identified an intronic 12-nucleotide poly(A) insertion ("PolyA(22)") before the terminal exon that was associated with seizure, "glazing over" behaviors, and episodic biting behaviors in a sample of 138 Malinois. We next investigated whether PolyA(22) was associated with 1) increased locomotor activity and 2) response to novelty. Using a sample of 22 Malinois and 25 dogs of other breeds, dogs' activity was monitored in a novel and non-novel environment while wearing activity monitoring collars. All dogs were more active in novel compared with non-novel environments, and Malinois were more active overall than other breeds. There was an effect of PolyA(22) genotype on activity levels, and this effect appeared to underlie the difference detected between Malinois and other breeds. There was no effect of PolyA(22) genotype on the relative decrease in activity between novel and non-novel environments for either group or all dogs considered together. In addition to an association between PolyA(22) and owner reports of seizure, "glazing over" behaviors, and episodic biting behaviors, these findings support an effect of PolyA(22) on dopamine transporter function related to activity. Further investigation is required to confirm mechanistic effects of PolyA(22) on SLC6A3. The complex polygenic nature of behavior and the range of behaviors associated with this insertion predict that effects are likely also modified by additional genetic and environmental factors.
authors.affiliation: Department of Animal Science, University of California Davis, Davis, California, United States of America.
authors.forename: Lisa
authors.initials: L
authors.lastname: Lit
authors.affiliation: Department of Animal Science, University of California Davis, Davis, California, United States of America.
authors.forename: Janelle M
authors.initials: JM
authors.lastname: Belanger
authors.affiliation: Precision Canine, Phoenix, Arizona, United States of America.
authors.forename: Debby
authors.initials: D
authors.lastname: Boehm
authors.affiliation: Left Coast K9, Marysville, California, United States of America.
authors.forename: Nathan
authors.initials: N
authors.lastname: Lybarger
authors.affiliation: Department of Animal Science, University of California Davis, Davis, California, United States of America.
authors.forename: Anita M
authors.initials: AM
authors.lastname: Oberbauer
mesh_terms: D000374:Aggression; D000818:Animals; D001483:Base Sequence; D001522:Behavior, Animal; D004285:Dogs; D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics*; D005091:Exons; D005106:Exploratory Behavior; D005260:Female; D059647:Gene-Environment Interaction; D056726:Genetic Association Studies; D005838:Genotype; D008297:Male; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D010641:Phenotype; D011061:Poly A / Q000235:genetics*
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D011061:Poly A