The Genetics of Autism: For Some Families, An Explanation At Last
Professor Eric Morrow spends his working life doing very different things.
One day, Professor Morrow—to be precise, assistant professor of both biology and psychiatry, member of the Brown Institute for Brain Science (BIBS), and director of the Developmental Disorders Genetics Research Program at Brown and Bradley Children’s Hospital—might be in a biochemistry lab. He’ll be peering at cell samples, or running a white machine that looks like a dorm fridge but can sequence an entire human genome in a matter of days. His research is helping cement the recent understanding that about 15% of autism cases can be tied directly back to DNA. It lands him big grants and frequent publications in peer-reviewed journals.
Different levels of analysis are vital, and they’re what BIBS does exceptionally well.
—Professor Eric Morrow
The next morning, he might be mentoring neuroscience graduate students. Or he might be in a treatment room with patients who run the huge gamut that exists in autism spectrum disorder (ASD) cases.
"What I do is BIBS in its essence," says Morrow. "To go from the classroom to the lab to the hospital, it's research without walls."
About half of Morrow's patients have intellectual disability—although others might test out with an IQ of 130—and some 25% suffer from epilepsy. They are 1 in 88 children, or 1 in 50 boys. The most profoundly affected among them have severe social, physical and intellectual deficits that will likely mean a lifetime of care.
As a researcher, Professor Morrow is intrigued by the huge differences between them. “Autism is a problem of the developing brain,” he explains. “So it’s a flashlight on how we acquire higher functions like language.”
But as a father, it’s the parents who linger in his mind. The genetic diagnosis he offers some is the first explanation they’ve received for why their child has atypical development—in fact, they’re the first explanations available for any ASD cases—and the impact can be profound.
One severely affected adult patient was diagnosed at a time when clinicians theorized that the emotional frigidity of mothers caused ASD. “Her parents have carried that with them for more than 30 years,” he says. But when he sequenced her DNA, he found a rare genetic condition called a 9q34 Deletion, or Kleefstra syndrome—one of dozens of genetic syndromes defined in just the last few years.
He called her parents immediately. “Now they know it wasn’t their parenting,” he says, “it wasn’t pregnancy nutrition or a childhood experience.” Another vital piece of information: “It was a spontaneous genetic event, so they wouldn’t have passed it on to other children.”
The long-term goal of Professor Morrow’s work is the holy grail of all ASD research: treatments that will improve cognitive functioning. He believes BIBS has a vital role to play. “Autism involves language and social cognition—some of the hardest things that brains do," he says. "So it’s among the hardest problems we have to solve. You start with modern genomics, then pull in stem cells, mouse models, neuro-imaging, and longitudinal patient studies. These different levels of analysis are vital, and they’re what BIBS does exceptionally well.”