There are many different forms of, and known causes of, autism. Navigating through them all is the mission of Geisinger's ADMI, or Autism and Developmental Medicine Institute.
At its headquarters near Lewisburg, officials hold special events dedicated to particular disorders. We got to sit in on one such clinic for patients who have something called Fragile X Syndrome.
Legally, 5-year-old Tarel and 3-year-old Nina are brother and sister. Biologically, they're first cousins. And mom and dad Joan and Tom Wynings of Northumberland say they share a very special bond, not to mention a genetic disorder called Fragile X Syndrome.
Joan says Tarel was the perfect baby right up until he was about five or six months old.
"When we went to his 6 month checkup, the pediatrician said, we have a problem. He's not trying to roll over, not pulling up his head," she remembers.
Therapists worked with Tarel for the next few years, but nobody had any answers about what was wrong with him. That is, until Nina came along.
"Her mother called us and said that she had been diagnosed with Fragile X," Joan says.
At the suggestion of their doctor, Joan and Tom had both kids tested, and it turned out both had Fragile X Syndrome. Joan recalls being instantly overwhelmed.
"I, of course, went right to the computer, looked it up, and thought- I don't know what to expect here. Are they going to grow up to be able to care for themselves?"
Fragile X Syndrome is the most common inherited cause of intellectual disabilities, according to Brenda Finucane, the associate director of ADMI, Geisinger's Autism and Developmental Medicine Institute.
"There are thousands of different reasons for autism, and many causes that we don't know. One of the most common causes that's known is Fragile X Syndrome," Finucane told us.
We met Finucane at the Geisinger-Bucknell Autism and Developmental Medicine Center near Lewisburg. She says Fragile X occurs in both genders, but generally girls have less severe symptoms.
"We now know that there are genetic underpinnings to most neurodevelopmental disorders, so in many cases we can figure out the cause and plug it into more customizable information," Finucane explained.
Several times a year, the center holds special clinics, so that patients and families with specific diagnoses can come together for lunch, to meet and to talk. This was Fragile X day, something the parents here say is invaluable as they all learn more together.
"It's so much help and so reassuring. There's someone else out there having the same issues," Joan told us.
Fragile X Syndrome is not only one known cause of autism, it's also associated with infertility in women who are carriers. Adult onset Fragile X can cause tremors, memory loss, and balance problems. If you think you or someone in your family should be tested, talk to your own doctor.