New treatments for a rare genetic disorder may hold clues for treating autism, researchers said Thursday at the International Fragile X Conference held at Union Station.

Fragile X syndrome is a common inherited cause of cognitive impairments, including about 5 percent of autism cases. Symptoms can include hyperactivity, seizures, learning disabilities and speech delays.

About one in 4,000 boys and one in 6,000 to 8,000 girls are born with the Fragile X, according to the Centers for Disease Control and Prevention.

Because the disorder can be linked to a defect in a singular gene, it's a promising field of study for researchers. At the weeklong conference sponsored by the National Fragile X Foundation, St. Louis hosts several hundred parents, physicians and researchers looking for the latest developments in treatments and patient support.

Typically, treatment for Fragile X includes medications that treat behavioral symptoms. Researchers are now working on the underlying disorder that over-stimulates the nerve pathways in the brains of people with the syndrome and those with autism.

Drug therapies that block those pathways are still experimental. To date, there have been no large clinical trials in Fragile X patients. The small studies have shown some promise, however.

"It's been the first conference where the promise of powerful new treatments is literally around the corner," said Robert Miller, the foundation's executive director. "There's just a lot of hope and excitement because everybody's picked up on the buzz."

One drug, the mood stabilizer lithium, corrected hyperactivity and reduced seizures in mice. In a two-month trial in 15 children, behavioral symptoms improved in 13 patients after two months, but IQ levels did not change.

Other drugs mentioned at the conference included oxytocin, a mood-enhancing hormone, and minocycline, an antibiotic that shows promise in reducing symptoms of mice treated in infancy.