Scientists at the Lieber Institute for Brain Development in Baltimore say they may have figured out how a rare form of autism called Pitt-Hopkins syndrome develops from a gene mutation, and they plan to begin testing a potential treatment soon.
The scientists at the Johns Hopkins University-affiliated, independent laboratory, don't expect they've found a cure but believe children especially could see significant improvements in their intellectual, developmental and communication deficits.
If the treatment — an existing drug intended to treat pain — is effective, it could be tried on similar syndromes on the autism spectrum, as well as schizophrenia, which is associated with the same gene mutation, Lieber officials said.
"Across the world, people are trying to understand autism," said Dr. Daniel R. Weinberger, director and CEO of the Lieber Institute. "If we can really dissect what is happening in the brain with a very specific disorder, it gives us insight into what's going on in the autism brain."
In this case, scientists studied the gene mutation in rats and found it creates alternative channels in the brain that interrupt normal cell activity. The channels are proteins on cell surfaces that normally carry information in the form of electrical impulses.
But in Pitt-Hopkins, these channels instead disrupt cell activity so the brain doesn't respond properly to stimuli in the environment and allow people to speak or respond to social cues, for example.
Much of the past research on Pitt-Hopkins and other autism disorders have centered on correcting the specific mutated gene, but at Lieber the investigators, led by neurobiologist Brady J. Maher, aimed "to correct the mischief this abnormal gene is causing in the brain," Weinberger said.
Once they discovered the responsible channels, the researchers looked for a drug to block them. They discovered there was one being investigated for use on chronic pain that worked by blocking the channels causing havoc. When Lieber scientists used it in their lab rats, cells began acting normally.
The findings may have implications beyond Pitt-Hopkins, for which there are about 500 confirmed cases, though the that number is likely low, said Rebecca D. Burdine, an associate professor in the department of molecular biology at Princeton University.
It would be tough to say what restoring normal cell activity would do in a human brain and how many deficits could be restored, said Burdine, also head science adviser for the Pitt Hopkins Research Foundation, which helped fund the Lieber Institute's research, and the mother of a child with a similar syndrome.
She said, however, there is a chance that children could learn to talk, for example, and begin to catch up in other ways because the brains of Pitt-Hopkins children haven't developed abnormally.
"Saying the neurons aren't functioning correctly is different than [saying] the brain didn't develop correctly," she said. "This is like a car and all the pieces are there, but the engine isn't firing correctly. … Potentially, you can fix the engine if you know what's wrong."
Audrey Davidow Lapidus, president of the Pitt Hopkins Foundation and the mother of a 5-year-old with the syndrome, said she is hopeful that trials can begin quickly and that they will show improvements.
But, she said, she understands that something promising in the lab doesn't always work in humans.
"Certainly this is hope," she said. "There are no treatments now."