"He went from passing at 18 months with flying colors to failing with flying colors at the two-year check-up," said Charlie Di Bona about his now six-year-old son, Miles.

The signs were apparent even before Miles turned two.

"It's almost like a light switch went off. It's like I went in one day and I said, 'Good morning Miles' and he said 'Mama' to the next day not even responding," said Jenn Di Bona.

The Di Bonas thought that it was hearing loss. It wasn't. It was autism.

"It's a huge shock to the system to deal with. It's sort of akin to a death," said Charlie.

Fortunately Miles was diagnosed earlier than most, so he could benefit from early intervention. Still. treatment remains a guessing game.

"We don't have again any clear biological markers that say, oh Joey you need this type of treatment and Billy you need this type of treatment. We don't have anything like that yet," said Raphael Bernier, PhD, director of Seattle Children's Autism Center.

That's what a new study funded by the National Institutes of Health is hoping to uncover: the biomarkers that are evident even before the symptoms of autism appear.

"Had we been able to start that early intervention before age oneā€¦.I think where he is now, he would have been there two years ago." said Jenn.

Dr. Bernier said the long term goal is even more ambitious.

"That if we intervene early enough before symptoms even emerge, we can actually change the trajectory so those kiddos never go on to develop autism," said Dr. Bernier.

For the Autism Biomarkers study, researchers will be recruiting children four to 11 years old, both of those with autism and those without.

Besides the University of Washington/Seattle Children's Autism Center, other study sites include Yale, Duke, Boston Children's Hospital and UCLA.

Resource links:

Yale Center for Clinical Investigation - Autism Biomarkers Consortium for Clinical Trials