WESTBROOK — Dr. Matthew Siegel is on a mission to unlock the secrets of children with autism.

“There’s this big gap in the scientific research,” said Siegel, of MaineHealth’s Spring Harbor Hospital in Westbrook. “What the differences are between an autistic child with a high IQ who has communication skills and a kid who doesn’t speak at all and has problems with basic functioning, we don’t know.”

But soon, Siegel and a team of researchers will study the most severely affected autistic children, thanks to a two-year $1.2 million grant provided by the Simons Foundation and the NLM Family Foundation.

Siegel said the grant, which has already resulted in five research-related jobs created in Maine, could lead to more autism research money flowing to the Pine Tree State. The research has the potential to be groundbreaking, Siegel said, because it could lead to more effective treatments for autism.

Spring Harbor and Maine Medical Center Research Institute will direct the research, which will also include hospitals in Rhode Island, New Hampshire, Baltimore, Colorado and Pittsburgh. In all, about 500 to 1,000 children will be studied and tracked over time.

“Maine will be at the center of this national research, when usually names like Yale, Brown and Duke (universities) come up,” Siegel said. “I think it’s remarkable that we can be a part of that.”

Siegel, director of the developmental disorders program at Spring Harbor, said the population of children with autism admitted at Spring Harbor provided the inspiration to apply for the research grant.

He said the children admitted for 30-day or longer overnight treatments at Spring Harbor — often because they’ve became too aggressive or were trying to hurt themselves — also typically represent the most severe autism cases. Siegel said he noticed that the lack of research on low-functioning autistic children, and that inspired him to apply for the grant.

“I’m so hopeful that with this research we can help the kids who need the most help, the children that we understand the least,” Siegel said.

Siegel said participants in the study will have blood drawn for genetic analysis. Also, researchers will administer intelligence tests, study the children’s behaviors, ability to regulate emotions and communicate.

“What we are trying to determine is whether we can define subgroups within the autism spectrum,” Siegel said.

He said the research could eventually lead to more effective medicine and behavioral-based treatments, and the genetic research could help doctors determine causes of autism.

Any practical improvements for families affected by autism would be welcome, said Cathy Dionne, who heads the Autism Society of Maine, a nonprofit advocacy and support group.

Dionne, whose 19-year-old son Benjamin is autistic and does not speak, said that even though Maine has more resources for children with autism than many other states, it’s still a struggle. She said the research money coming to Maine is good news, and hopefully it can spur more improvements to the system.

“It’s daunting what families have to go through,” Dionne said. “There’s not enough support for families.”

Dionne, of Greene, said although the study focuses on children, they eventually become adults, and anything that can be done to help those with autism to lead better lives will be much appreciated.

She said that her son, even though he has difficulty communicating, would likely land an agricultural job bagging seeds and live as independently as possible.

Siegel, 41, of Yarmouth, said the goal is to one day be able to diagnose and prescribe treatments that work.

“My dream is we would play a role in reaching that point,” Siegel said.