After running lab tests, they learned that some of Clarke's genes had an extra copy -- part of chromosome 16 had three copies, instead of the usual two. With that knowledge, Bordelon knew that while the disease originated in Clarke's genes, it was not something she could have controlled.
"Now, I feel... it wasn't something I did. It's more a problem after fertilization, when he started dividing, that chromosome made three instead of just two," said Bordelon. "I wish it had been available earlier, that we would have known."
Doctors also note that by knowing a child has autism earlier, intervention to aid in behavior can have greater effects. As genetics researcher will frequently note, genes are not destiny.
Bordelon is one of many parents benefiting from the increase in autism research of recent years. And while many researchers are looking at genetic origins -- which in some cases are known -- others are looking at the less developed area of environmental causes for autism.
"We think autism has a very strong genetic component. To what extent environmental factors influence autism is not fully understood," said Dr. Walter E. Kaufmann, director of the Center for Genetic Disorders of Cognition and Behavior at Kennedy Krieger Institute in Baltimore.
"That's not because environment doesn't play a role, but because we don't have the data yet," Kaufmann said. "It could be environmental factors, but we don't know that yet."
He estimates that doctors can determine the origin of between 30 percent and 50 percent of all autism cases. But he emphasizes that is not the same thing as knowing the cause.
"The problem has been, and continues to be ... there is no one cause that anyone has isolated for autism," said Katherine Loveland, a psychologist who is director of the Center for Human Development Research at the University of Texas - Houston Medical School.
That cause -- the pathway the proteins take from the gene's orders to causing the disease -- may be the key to a cure.
Because of how complex autism is as a disease, breakthroughs may be piecemeal.
"We're not going to find a single cause and we're not going to find a single cure," said Loveland.
But at the same time, Loveland and other researchers are optimistic that with the influx of money and minds to the field of autism research, those advances will come.
"I'm confident that we're going to make some breakthroughs in autism in the next 10 or 12 years," she said.
In recent months, research has given even more clues to autism's roots. In July, Harvard researchers published a study linking specific genes to processes in the brain that control learning and memory. Studies like this may give researchers better clues into how autism operates and insight into how to counteract it.
And that sense of hope among researchers is also felt among parents.
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"I think it's exciting because I think when they find out more, they'll know how to help my son better," said Bordelon.