Scientific research over the past 30 years has revealed a patchwork of potential causes of autism. Most of them are genetic—the condition is between 60 and 90 percent heritable—and some involve nongenetic risk factors that might impact development during pregnancy.
“We’ve found a great deal of the underlying [causes],” says Helen Tager-Flusberg, an autism researcher and a professor emerita at Boston University. But how these different risk factors come together as the brain develops remains a challenge to piece together. “Autism is not a simple disorder,” she says. “There are no simple answers. There are no so-called smoking guns.”
Even so, Robert F. Kennedy, Jr., the U.S. secretary of health and human services, talks about autism in a way that suggests he thinks there are simple and direct causes. He often refers to the steady rise in autism prevalence (which is likely due to improved screening and diagnosis) as an indicator that we’re in the middle of an “autism epidemic” driven by “environmental toxins.” He has also refused to disavow the long-debunked idea that vaccines cause autism. This month, as part of Kennedy’s effort to find “the root causes of autism,” the National Institutes of Health and the Centers for Medicare & Medicaid Services announced that they will create a “data platform” to study the condition. In April NIH Director Jay Bhattacharya had described plans for “national disease registries, including a new one for autism.” The plan involved collecting “comprehensive” private health data on autism that would represent “broad coverage” of the U.S. population, leading autism advocacy organizations, civil rights groups and research scientists to warn of medical privacy concerns. (Shortly after outlets reported on Bhattacharya’s statements in April, HHS denied that it planned to create an “autism registry.”)
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In a budget hearing on Wednesday, Kennedy called for an end to genetic research into autism. “I don’t think we should be funding that genetic work anymore,” he said. “What we really need to do now is to identify the environmental toxins.”
In response to this dismissal of well-established science, Tager-Flusberg has organized a coalition of scientists to push back. The Coalition of Autism Scientists now has 258 members and is still growing.
Scientific American spoke with Tager-Flusberg about Kennedy’s statements this week and how the autism community is responding.
[An edited transcript of the interview follows.]
In a Congressional budget hearing Wednesday afternoon, Robert F. Kennedy, Jr., said: “Autism is an epidemic, and the genes do not cause epidemics. They can contribute a vulnerability, but you need an environmental toxin. It’s like cigarettes and smoking.” What was your reaction to that?
There is no reason that we need to refer to the increased prevalence rates, which have been rising steadily for many years now, as an epidemic. This is not the definition of an epidemic, so I take issue with highlighting that.
Second of all, genetics are the primary contributing factor to autism. We know specific genes and variants confer increased risk, even in cases where there aren’t any clear environmental contributions. If anything, it’s the other way around—it’s the environmental factors that add to or interact with the genetic risk for autism.
Take one of the very well-regulated nongenetic factors: parental age, particularly paternal age. What we think is going on is that, as parents age, their germ cells [which develop into eggs or sperm] are changing, and so this is leading to alterations in the DNA that then confer risk for autism.
Are there other nongenetic factors that might be playing a role?
[Studies have shown] that [pregnant] mothers who take an antiseizure medication, particularly valproic acid, can have an increased risk of having a child with autism. But here, again, we have to think about this in a more complex way. [In such cases], the mother herself has a seizure disorder, and seizure disorders are a very common co-occurrence with autism. So then [the parent and the child] well may have some shared genetic risk factors that are interacting with the effects of the medication itself.
When RFK, Jr., said “environmental toxins” are causing autism, do you think he was talking about vaccines?
Well, I listened very carefully to his testimony [on Wednesday]. And he will not rule out adverse effects of vaccines. And so, yes, I think he is probably still keeping that on his agenda. And you have the NIH director [Jay Bhattacharya] saying that we should look at everything because we want to gain the trust of people. To me, that’s not the way of gaining people’s trust. You don’t gain trust by saying that we can just toss out all the research that we’ve done so far and start again.
Why did you decide to form a coalition of autism scientists?
Colleagues of mine were becoming increasingly concerned, and we were thinking about what we could do as scientists. It came to a head for me when I saw all the advocacy groups—self-advocates, the parent advocacy groups, nonprofit organizations—come together and issue a very strongly worded and clear statement of concern about what they were hearing from the administration. And I felt that it was really important for the voice of scientists to be heard, too.
So I just contacted a small group of my colleagues and said, “I think we need to issue a press release.” I set up the Zoom call that afternoon, at five o’clock on a Friday. And it took off so rapidly. Clearly, there was a need for the voices of scientists to be heard. We have something very important to contribute because that’s where we have devoted our careers.
What has concerned you and your colleagues the most?
I would say there are probably four things. One is dismissing all the prior science that has been accomplished and everything that we do know. That, I think, is very disturbing.
A second [concern] is that, at no point over the past several months of this administration, has the secretary of health and human services or, [since he took office on April 1], the NIH director reached out to anyone we know in the external autism science community. They have not reached out to us at all, and I think that is very disturbing.
A third thing is that the one person that was named early on [by the administration to lead research into autism] was David Geier, who is not a trained scientist. [Editor’s Note: Geier is a long-time vaccine skeptic. He is not a physician and was sanctioned in 2011 for practicing medicine without a license.]
The fourth thing is that now, we heard last week, the administration plans to use Medicare and Medicaid data as the foundation of the research plan to uncover the “roots” of autism. These are not databases that are suited to that kind of research because they capture only a subset of children diagnosed with autism. And there are serious concerns about whether this administration would put into place and commit to the kind of ethical privacy and confidentiality attempts that are needed to conduct this.
Many autistic people push back on this focus on finding the “roots” of autism or a “cure.” How does that pushback fit in here?
Autism is an enormously heterogenous disorder. People who, while needing some support, still can function and flourish individually represent one end of the spectrum. They can speak for themselves, and for at least some of them, autism is part of their identity. And understandably, they are not interested in a cure—and parenthetically, it’s unlikely that one could even identify a potential cure.
But autism also involves the other end of the spectrum. A quarter to a third [of people with the diagnosis] are far more severely impaired. They may have limited daily living skills; they cannot be left alone; they have extremely limited communication abilities. This is the end of the [spectrum] that we now call profound autism. It is such a challenge for them and their families, especially some of them who engage in self-injury or very aggressive behavior. Yes, I think there is hope that we might find maybe not a complete cure but something that would significantly change their developmental course. I think we should be able to hold both ideas in our head at the same time because this is the reality of what autism is.
Kennedy’s approach seems to step right on that fissure in the autism community. Is there a way to prevent this rift from developing further?
I don’t think I have the answer to that. It’s a big question in the community because people are looking at the agendas in very different ways. But I will say one thing. I have been really impressed, over the past couple of weeks, since beginning this coalition, with how [autistic] folks who are self-advocates have joined the coalition. I think the one thing that unifies us is a belief in the importance of scientific research. Maybe we define the scope of that science in different ways, but that’s always true. That’s something that we all hold to.
And I think we all, at this moment, believe that the direction that’s been described so far by the administration is not the way we should go. We should not be opening up the question of vaccines again. We should be very cautious about using “registries” and make sure the research that’s done is ethical and maintains the confidentiality of individuals in those databases. We all agree about that.
We also all agree that, so far, we’re not hearing from the administration that they have a very deep understanding of autism. They have failed to engage most of us, whether scientists or advocates or nonprofit organizations. None of us have been involved in these discussions. So I think we actually have a moment in time where there is some agreement, and I think it behooves the administration to think about why that is and whether they need to change their course.
