SLC6A3 and Seizure: For example, a single copy allele of a variable number tandem repeat (VNTR) and an intronic 12-nucleotide poly (A) insertion in the dopamine transporter gene (SLC6A3) are associated with owner-reported seizures, loss of responsiveness to environmental stimuli, episodic aggression, and hyper-vigilance in the Belgian Malinois dog breed [18].