Understanding the Biology of Autism
Peter Penzes, PhD, says the field of autism neurobiology is ripe for discovery and his team at the new Center for Autism and Neurodevelopment at Feinberg is laying the groundwork for new treatments for the disorder.
"What we learned is that not all this genetic risk is inherited. Many are called de novo mutations, which occur in the parent and are transmitted to the child. We also learned that probably hundreds or maybe even thousands of genes contribute to autism, but they contribute in a very complicated way."
— Peter Penzes, PhD
- Director, Center for Autism and Neurodevelopment
- Ruth and Evelyn Dunbar Professor of Psychiatry and Behavioral Sciences Professor of Physiology and Psychiatry and Behavioral Sciences
One in 68 children has some form of autism spectrum disorder. The number of cases has spiked in recent years. The new Center for Autism and Neurodevelopment at Feinberg is focused on understanding the biological bases of autism and neurodevelopment disorders and using this knowledge to develop treatments.
Peter Penzes: "One of the main goals of the center is to understand what the normal functions of these genes that have been implicated in autism are in the brain and what mutations in these genes do to the brain circuits during development. And what we learned is that not all this genetic risk is inherited. Many are called de novo mutations, which occur in the parent and are transmitted to the child. We also learned that probably hundreds or maybe even thousands of genes contribute to autism, but they contribute in a very complicated way."
When some of these genes have severe mutations, they can increase autism risk. One of the main goals of the center is to educate the public about genetic mutations and how this information can be used to develop treatments that are better suited to individual patients.
Peter Penzes: "Autism is a spectrum disorder, which actually means that no two children with autism are alike, so their genetic mutations and their environmental contribution are all different. Clinical trials and development of new drugs for autism have been really made difficult because of this heterogeneity."
Penzes says he is interested in studying groups of patients based on their gene mutations versus their symptoms.
Peter Penzes: "When you group them based on mutations, you can develop or repurpose known drugs that treat that specific gene or mutation, not the symptoms. This is one of the goals of the center, is to identify patients that have mutations in a specific genetic pathway, group them into a study, a so-called basket trial, and try to repurpose drugs from other diseases or to develop new drugs for these subgroups of patients."
In addition to genetic mutations and genes that contribute to autism, there are also some environmental factors.
Peter Penzes: "Environmental conditions are thought to contribute to autism. For example, a maternal infection during pregnancy or a specific medication taken by the mother during pregnancy or drugs or chemical exposures, increase risk for autism. There has been a lot of hype and scare about vaccines causing autism. But, I would like to emphasize that has been shown repeatedly not to be the case.
Much of autism is de novo, meaning "the first time" or not inherited.
Peter Penzes: "In many cases, the mutations occur in the germ line cells of the parents, in particular in fathers. It has been shown that all their fathers have a higher risk of having such mutations. So, autism has actually been associated with an older age of the father, not the mother. So that means that mutations can occur in the sperm and be transmitted the children. So it's a genetic mutation, but it's not inherited through many generations."
Another interesting aspect of the disorder is that boys are diagnosed with autism more often than girls.
Peter Penzes: "It's not very clear why, but the ratio seems to be 4:1, boys to girls. The reasons might be complicated. ... Girls are maybe underdiagnosed. ... Also, when you include other factors in the diagnosis such as intellectual disability, the ratio could change to 2:1."
The center is also looking closely at an overlap in autism and epilepsy and what it means.
Peter Penzes: "About 30 to 50 percent of children with autism also have seizures or epilepsy. And at Northwestern there is a very strong group of epilepsy scientists and clinicians, and many of the patients they see for epilepsy actually turn out to also have autism. Many genes that cause epilepsy also cause autism and vice versa. So, we think that by understanding the genetic and neurobiological causes of this childhood epilepsy, we can also understand the biology of autism and by potentially repurposing drugs that treat ion channel dysfunction or seizures, we could potentially address the behavioral symptoms of children with autism."
The center is now teaming up with organizations such as Autism Speaks for seminar series, which will be open to the public.
Read more about the new center and Penzes work. Back to top