We have tests for the speed gene, white gene, overo lethal white foal syndrome, and polysaccharide storage myopathy type 1, as well as genetic panels required for registering Arabians and Quarter Horses. Now, researchers might have discovered a gene that could identify superior tractability—which simply refers to how easily an animal can be trained or controlled—in horses.

“Our research shows that one type of serotonin receptor called serotonin receptor type 1A, or HTR1A, may affect tractability in horses, making those with a particular form of the gene easier to train and handle,” explained Yusuke Hori, PhD, from the Department of Psychology at Kyoto University in Japan.

Serotonin is an important neurotransmitter in the brain that is widely believed to play a role in mood, depression, memory, and learning. For example, human research shows that one specific mutation in HTR1A increases the risk of depression, suicide, and panic disorder. In horses, the role of HTR1A remains less clear.

In their study, Hori and colleagues sought to better understand THR1A by evaluating 167 Thoroughbred racehorses using a 17-item questionnaire and sequencing of the HTR1A gene