'Significant Overlap': Researchers Work to Understand Connection Between Autism and Gender Fluidity

As a toddler, Izzy Dier hated sundresses and loved Hot Wheels sneakers.

“I had a hunch, always, that I was way more masculine than my other female peers,” said Dier, who uses she/they pronouns.

As early as preschool, Dier started questioning her gender. When she was a teenager she began wondering if her testosterone was higher than average.

“I always had bushy facial hair and these little spots on my chin,” she said.

The 23-year-old now identifies as gender-fluid. She clutches her rainbow-colored purse as she leans back on a bench in Buena Vista Park. This spot under towering oak trees is Dier’s favorite place in San Francisco. Normally when she’s walking around or driving, she wears headphones.

“Otherwise my anxiety spikes and I just can't help but gasp at every little thing,” said Dier. “And just like jitter and jolt.”

When Dier was 3 years old, she was diagnosed with autism. Her preschool teachers noted that she was impulsive and hyperactive.

People who are transgender or nonbinary are more likely to be autistic. One large study found that it’s three to six times more common than in the general population. Researchers are working to understand the connection and exploring how society can be more accommodating to people who live at this intersection.

“We see that there is a pretty significant overlap in both directions,” said Dr. Aron Janssen, a psychiatrist at Northwestern University's Feinberg School of Medicine. In other words, it’s also more common for people who are autistic to question the sex they were assigned at birth.

“Maybe there is something that is related to biology like hormonal differences,” said Dr. Lawrence Fung, a psychiatrist at Stanford University. “Females on the spectrum seem to have more testosterone, and masculine features on their faces. On the other hand, males on the autism spectrum, they have more feminine features.”

For example, clinicians have noticed that male patients with autism often have a high-pitched voice, and research shows that female patients with autism tend to have increased facial masculinity.

Fung’s research also shows that the brains of autistic men and autistic women are different. The part of the brain responsible for sensory and motor functions may hold the key to this sex difference. Eventually neuroscience could help explain why people with autism are more likely to question their sex assigned at birth. There is a clear overlap between these groups, but a lot more research is needed to understand the roots of it.

Danielle Sullivan is curious about what scientists will discover about her lived experience.

“I didn't really like being a woman,” said Sullivan. “I didn't feel like a woman. I don't really feel like a man or male either, which is why I've sort of settled in the agender bucket.”

Sullivan is autistic. The 37-year-old counsels others on the spectrum in Lafayette, Colorado, as a neurodiversity coach. When she was diagnosed with autism five years ago, Sullivan felt relieved because it explained why she had always felt a little like an outsider.

“A lot of people seem to have a handbook that I had missed somehow for things like how to date, how to talk to people, how to dress,” she said.

Today Sullivan is comfortable in her own skin as an agender or nonbinary person with autism, but her childhood was challenging.

“I felt like I was failing constantly and like I just couldn't do it. There was just some kind of internal brokenness about me,” she said.

Sullivan wishes society was more accepting and more accommodating of people with autism. She has two children who are both on the spectrum.

“One of their quote-unquote behaviors: They're yelling, they're shaking their hands, they're rocking. It's like, ‘They're fine. They're happy. Leave ‘em alone.’ I just wish there was less judgment around that and more curiosity and interest,” she said.

She says the autistic brain is not a problem or something to be feared. In many ways, she says, her mind is more open and less hindered by societal norms and expectations.

Many experts say the psychology that Sullivan is pointing to may be driving the overlap between autism and gender identity.

“Autistic people take in and process social information in a somewhat different way than neurotypical folks,” said John Strang, director of the Gender and Autism Program at Children's National Hospital in Washington, D.C. “And because autistic people may be less moored and less yoked to social expectations, this means that they also might be less yoked to social gender roles.”

Janssen agrees, saying, “Some of the strengths that many people with autism have is looking at systems that are done because we've done them that way forever and calling it out as BS. People with autism can easily say, ‘This doesn't make sense to me. This isn't my experience.’”

That is definitely true for Izzy Dier back in San Francisco sitting at Buena Vista Park.

“There's something about having a place on the spectrum and feeling othered by the world, but still just being here no matter what, that really does … strengthen your skin.”

Dier says her uniquely wired brain and her gender fluidity are her greatest gifts because together they’re the roots of her resilience.

For many clinicians treating nonbinary or transgender people with autism, the cause behind their unique life experience is not crucial to providing excellent care.

“At the end of the day, it's really about helping people live self-actualized lives, where they're able to make choices and communicate those choices effectively,” said Janssen. “We need a health care system that is responsive to however those needs are communicated.”