Autism affects 1 in 68 people, according to the CDC’s autism monitoring network. Chances are that you probably know someone with Autism, and have seen its effects firsthand. Autism has been called a uniquely human disorder, as in it may be one of the only disorders that is solely found in humans. For me, this brought up the question: are there animals that have autism? And if not, then why is it just humans that we see the disorder in?
Scientists went looking for any animals that might display some of the behavioral characteristics that are typical of Autism Spectrum Disorder (ASD) individuals. The problem with this is, how do you know if you’ve found autism? Autism can 
unfortunately still be somewhat difficult to diagnose from a very young age, and so if we as humans have issues diagnosing it within ourselves, it could be even more difficult to actually pin down when observing an animal.
Researchers also specifically looked at several different species such as dogs, cats, and monkeys, which have more similarities with humans than some animals would. Although most of the animals they looked at had inconclusive symptoms, they did 
discover similarities in a breed of dog called Bull Terriers, which they found to display some of the (dog equivalent) behaviors that can be diagnosed as autism in humans. I say “dog equivalent” because some of the staple behaviors of ASD are very difficult to distinguish in animals that can’t talk, such as imparied social interaction and not being able to communicate properly, which in humans can manifest as an inability to formulate speech or something similar.
These Bull Terriers were found to avoid other people and dogs at a rate that was higher than most other breeds. Another common behavior found in autism is performing repetitive or ritualistic behaviors, and these dogs would also chase their tails for an abnormal amount of time. I know this sounds strange, as in, “so what, the dog is just chasing their tail, they do that”. But if you think about it, if you saw a dog that was chasing its tail for over twenty seconds, (count that out and imagine it if you need to) it stops being cute and playful and starts becoming a little worrisome. These dogs would also have outbursts of anger, another behavior found in autism. This is along with all of these behaviors being found in predominantly male Bull Terriers, which is how also the case with human ASD.
Now, behaviors by themselves don’t signify autism, so researchers needed some sort of biomarker that they could actually measure to see if physiology of these dogs also matched some of the physiological effects found in humans with ASD. Specifically, they looked at Neurotensin (NT) and Corticotropin-releasing hormone (CRH) levels in Bull Terriers, as they have been found to be elevated in humans with autism. What they found was that the results (levels) in dogs were similar to that of humans, which is an amazing piece of evidence that links up not 
just the behavioral aspect of autism with animals, but also potentially the physiological side of things too.
But why does it matter that some Bull Terriers might have the dog-equivalent of autism?
To be able to more effectively learn about, treat, and live with autism (or almost any disorder for that matter), scientists use animal models to be able to figure out things about how these disorders operate. Using animals as test subjects (for the advancement of science), we can further understand how autism might arise genetically, or how to treat its symptoms once it does come about. One of the main goals with treating autism is to try give the individual as normal of a life as they can live, and so using this breed of terrier to try figure that out could improve the lives of countless people with ASD (including the dogs too!). Knowledge is power in the world of science and medicine, so being able to aid with a disorder that has plagued so many would be a worthy achievement.
