CNN
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Some people with autism have difficulty processing the senses. Others struggle to communicate. Still others may have difficulty socializing, thinking, moving physically, or just carrying out daily life.
People with autism have their own ways of interacting with the world, because autism is a developmental disability that affects everyone with it a little differently, according to Dr Daniel Geschwindthe distinguished Gordon and Virginia Macdonald Professor of Human Genetics, Neurology, and Psychiatry at UCLA.
Geschwind has spent 25 years studying autism and its causes. Tick autism awareness month CNN spoke to him about what autism is and what causes it.
This conversation has been lightly edited and abridged for clarity.
CNN: What is autism?
Dr Daniel Geschwind: Autism refers to a wide range of conditions characterized by challenges with social skills and social and communication and repetitive behaviors, resistance to changes in routine, or restricted interests. I prefer to call it “the autisms”, because it is not a single thing, and no two autistic children or adults are exactly the same, even though they may share basic characteristics. People with autism may also have some sensorimotor integration problems, especially sensory hypersensitivity.
CNN: How prevalent is autism today?
Geschwind: It is not strange. The most recent statistics (from the US Centers for Disease Control and Prevention. in March, it pulled data from 11 sites (in the US) and reported that 1 in 36 children is autistic. The previous study estimated about 1 in 40. About 10 years ago, the autism rate was 1 in 100or even lower.
It would be easy to look at this trend and say that autism is on the rise, but that’s not really what’s happening. The most recent data reflects that our ability to recognize autism and diagnose it early has improved dramatically. We can now diagnose people with autism that might have been missed (previously).
Everyone is neurodivergent to some degree. For example, if you look at a simple IQ test, a substantial portion of people will perform very poorly on a specific item. That doesn’t mean they have problems, it just means we all have strengths and weaknesses.
If I were being tested for artistic ability, for example, or engineering ability, it would be well below what’s called typical. I think we have to accept that intelligence is not just one thing, that cognition is not one thing, that there is not just one way to behave.
CNN: What does it mean when people describe some as “on the spectrum”?
Geschwind: About a decade ago, the term “autism spectrum disorder” was adopted to encompass everything we call autism under one rubric. The intent was simply to describe the variability in the way people with autism act and behave biomedically. There are some autistic people who just need accommodations and don’t need treatment. There are other autistic people who need a lot of treatment. The spectrum was meant to include them all.
Over time, non-autistic people began to refer to the spectrum in a linear way: from highest to lowest. That means some autistic people were classified as “high-functioning” while others were classified as “low-functioning.” For many, the notion of spectrum is now a loaded term. Many believe that instead of talking about autism in a linear fashion, we should talk about it like a wheel or a pie, with each slice representing a different trait and each individual having different strengths and weaknesses.
CNN: Is there a cure for autism?
Geschwind: There is no cure. At the same time, we have come a long way in understanding what autism is and are making progress in how to treat it. When I started researching autism 25 years ago, the rate of autism was 1 in 1,000 or 1 in 2,000. To put it in deeper historical perspective, I think at that time there were only about $10 million a year or less in autism research fact that was funded (by the National Institutes of Health). And so, there was a huge disconnect between research dollars, public awareness, and the real needs of patients and their families.
The notion of the term “curing” autism can be controversial. From my perspective, our real goal is to establish a kind of personalized medicine, or precision health in autism and other neuropsychiatric disorders, so that each autistic person is seen as the individual that they are. We envision a world in which people severely affected by autism have the opportunity to receive therapy and medications that can help them, and those for whom therapy is not warranted or do not want it, will have the opportunity to live life the way what they want I want too. Patient autonomy and social accommodation are important aspects when considering these issues.
CNN: What causes autism?
Geschwind: Almost all medical conditions have genetic and environmental components. In autism, the heritability seems to be very high. The latest big study suggested that hereditary genetic factors, the things you get from your parents that your parents have in their DNA, are probably somewhere around 80% or slightly higher.
That leaves 20% that is not heritable, and we know that at least 10% of autism is caused by rare mutations that are not inherited. And that sounds like a paradox, but it’s not. If you think about Down syndrome, it’s a genetic mutation that parents don’t have in their DNA. This is called a new or de novo mutation.
You can calculate an autism risk score based on genetics, (but) right now, the autism risk score is not as predictive because we haven’t done enough research. For other conditions such as cardiovascular disease or certain types of cancer, risk scores are highly predictive because large numbers of people have been studied.
Even so, this autism risk score is strongly correlated with either a high educational level or a high IQ, which again speaks to the strengths associated with being autistic and highlights that we need to be more aware of the strengths that autistic people may also have. have to optimize their opportunities to achieve their goals or contribute to society.
There are also several environmental factors that have been shown to increase the risk of autism. One of them is maternal exposure to valproate, which is an anti-epilepsy drug. There are several maternal viral infections that have been associated with autism. And two other things: the interval between births, how quickly after one birth a mother has another, and the age of the father. The idea on the last point is that as a man ages, his DNA repair mechanisms are perhaps less active and there are more frequent mutations in sperm.
A key point is that all of these known environmental factors are at work prenatally, so in most cases the tendency to be on the spectrum is something individuals are born with.
CNN: To what extent has research debunked the controversial notion that vaccines can cause autism?
Geschwind: The notion that vaccines cause autism has been totally (disproved). There have been dozens of studies, using very different methodologies. There is absolutely no evidence that vaccines cause autism, and the purveyors of that fiction have done far more harm than good.
CNN: How do you treat autism?
Geschwind: It is imperative to have an early diagnosis, because we know that early identification and early intervention with behavioral therapies can be effective in up to 50% of children. Some children will respond so well that it is very difficult to make a diagnosis of autism when they are 9 years old if therapy is started early enough.
The problem is that for many autistic people, current therapies are not as effective. Much work is being done to develop more effective cognitive behavioral therapies, determining which therapy is best for each child. Work is also underway to develop medications that may be helpful in treating certain symptoms, such as disruptive behavior, repetitive behavior, or difficulty with changes in routines.
My colleagues and I want to use treatment to augment and improve people’s symptoms, not to fundamentally change who they are. We firmly believe in the autonomy of each individual. We also believe in personalized medicine so that it is not the same for everyone. There will be some patients where we are trying to correct a severe genetic mutation that has far-reaching consequences, and there will be others who will only need a handful of accommodations, like the ones we provide for people who need wheelchairs.
CNN: What will your investigation focus on next?
Geschwind: There are two basic frontiers in my research. One acknowledges that most of the work in neuropsychiatric disorders and autism has been done primarily in white European populations and focuses on a pressing need to study diverse populations. About seven or eight years ago, I started working with African American communities because certain aspects of genetics are population specific and we as researchers really need to understand that.
The frontier that runs across all of this is that we need to be able to go from genetics in a population to genetics in an individual, so that by looking at someone’s genetic makeup, we can understand the mechanism of their autism. This is precision medicine.
My work is about understanding how specific genetic variants, how specific mutations, impact brain development to eventually lead to autism symptoms. If my colleagues and I can understand that mechanism, just like we can understand the genetic mechanism in cancer, we can find a drug to fight it and improve those symptoms over time.