Why Are Autism Rates Steadily Rising?
Stefania Sterling with her son Charlie, who was diagnosed at age 3 with autism.
Stefania Sterling was just 21 when she had her son, Charlie. She was young and healthy, with no genetic issues apparent in either her or her husband's family, so she expected Charlie to be typical.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period."
It wasn't until she went to a Mommy and Me music class when he was one, and she saw all the other one-year-olds walking, that she realized how different her son was. He could barely crawl, didn't speak, and made no eye contact. By the time he was three, he was diagnosed as being on the lower functioning end of the autism spectrum.
She isn't sure why it happened – and researchers, too, are still trying to understand the basis of the complex condition. Studies suggest that genes can act together with influences from the environment to affect development in ways that lead to Autism Spectrum Disorder (ASD). But rates of ASD are rising dramatically, making the need to figure out why it's happening all the more urgent.
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Indeed, the CDC's latest autism report, released last week, which uses 2016 data, found that the prevalence of ASD in four-year-old children was one in 64 children, or 15.6 affected children per 1,000. That's more than the 14.1 rate they found in 2014, for the 11 states included in the study. New Jersey, as in years past, was the highest, with 25.3 per 1,000, compared to Missouri, which had just 8.8 per 1,000.
The rate for eight-year-olds had risen as well. Researchers found the ASD prevalence nationwide was 18.5 per 1,000, or one in 54, about 10 percent higher than the 16.8 rate found in 2014. New Jersey, again, was the highest, at one in 32 kids, compared to Colorado, which had the lowest rate, at one in 76 kids. For New Jersey, that's a 175 percent rise from the baseline number taken in 2000, when the state had just one in 101 kids.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period," said Walter Zahorodny, an associate professor of pediatrics at Rutgers New Jersey Medical School, who was involved in collecting the data.
The study echoed the findings of a surprising 2011 study in South Korea that found 1 in every 38 students had ASD. That was the the first comprehensive study of autism prevalence using a total population sample: A team of investigators from the U.S., South Korea, and Canada looked at 55,000 children ages 7 to 12 living in a community in South Korea and found that 2.64 percent of them had some level of autism.
Searching for Answers
Scientists can't put their finger on why rates are rising. Some say it's better diagnosis. That is, it's not that more people have autism. It's that we're better at detecting it. Others attribute it to changes in the diagnostic criteria. Specifically, the May 2013 update of the Diagnostic and Statistical Manual of Mental Disorders-5 -- the standard classification of mental disorders -- removed the communication deficit from the autism definition, which made more children fall under that category. Cynical observers believe physicians and therapists are handing out the diagnosis more freely to allow access to services available only to children with autism, but that are also effective for other children.
Alycia Halladay, chief science officer for the Autism Science Foundation in New York, said she wishes there were just one answer, but there's not. While she believes the rising ASD numbers are due in part to factors like better diagnosis and a change in the definition, she does not believe that accounts for the entire rise in prevalence. As for the high numbers in New Jersey, she said the state has always had a higher prevalence of autism compared to other states. It is also one of the few states that does a good job at recording cases of autism in its educational records, meaning that children in New Jersey are more likely to be counted compared to kids in other states.
"Not every state is as good as New Jersey," she said. "That accounts for some of the difference compared to elsewhere, but we don't know if it's all of the difference in prevalence, or most of it, or what."
"What we do know is that vaccinations do not cause autism."
There is simply no defined proven reason for these increases, said Scott Badesch, outgoing president and CEO of the Autism Society of America.
"There are suggestions that it is based on better diagnosis, but there are also suggestions that the incidence of autism is in fact increasing due to reasons that have yet been determined," he said, adding, "What we do know is that vaccinations do not cause autism."
Zahorodny, the pediatrics professor, believes something is going on beyond better detection or evolving definitions.
"Changes in awareness and shifts in how children are identified or diagnosed are relevant, but they only take you so far in accounting for an increase of this magnitude," he said. "We don't know what is driving the surge in autism recorded by the ADDM Network and others."
He suggested that the increase in prevalence could be due to non-genetic environmental triggers or risk factors we do not yet know about, citing possibilities including parental age, prematurity, low birth rate, multiplicity, breech presentation, or C-section delivery. It may not be one, but rather several factors combined, he said.
"Increases in ASD prevalence have affected the whole population, so the triggers or risks must be very widely dispersed across all strata," he added.
There are studies that find new risk factors for ASD almost on a daily basis, said Idan Menashe, assistant professor in the Department of Health at Ben-Gurion University of the Negev, the fastest growing research university in Israel.
"There are plenty of studies that find new genetic variants (and new genes)," he said. In addition, various prenatal and perinatal risk factors are associated with a risk of ASD. He cited a study his university conducted last year on the relationship between C-section births and ASD, which found that exposure to general anesthesia may explain the association.
Whatever the cause, health practitioners are seeing the consequences in real time.
"People say rates are higher because of the changes in the diagnostic criteria," said Dr. Roseann Capanna-Hodge, a psychologist in Ridgefield, CT. "And they say it's easier for children to get identified. I say that's not the truth and that I've been doing this for 30 years, and that even 10 years ago, I did not see the level of autism that I do see today."
Sure, we're better at detecting autism, she added, but the detection improvements have largely occurred at the low- to mid- level part of the spectrum. The higher rates of autism are occurring at the more severe end, in her experience.
A Polarizing Theory
Among the more controversial risk factors scientists are exploring is the role environmental toxins may play in the development of autism. Some scientists, doctors and mental health experts suspect that toxins like heavy metals, pesticides, chemicals, or pollution may interrupt the way genes are expressed or the way endocrine systems function, manifesting in symptoms of autism. But others firmly resist such claims, at least until more evidence comes forth. To date, studies have been mixed and many have been more associative than causative.
"Today, scientists are still trying to figure out whether there are other environmental changes that can explain this rise, but studies of this question didn't provide any conclusive answer," said Menashe, who also serves as the scientific director of the National Autism Research Center at BGU.
"It's not everything that makes Charlie. He's just like any other kid."
That inconclusiveness has not dissuaded some doctors from taking the perspective that toxins do play a role. "Autism rates are rising because there is a mismatch between our genes and our environment," said Julia Getzelman, a pediatrician in San Francisco. "The majority of our evolution didn't include the kinds of toxic hits we are experiencing. The planet has changed drastically in just the last 75 years –- it has become more and more polluted with tens of thousands of unregulated chemicals being used by industry that are having effects on our most vulnerable."
She cites BPA, an industrial chemical that has been used since the 1960s to make certain plastics and resins. A large body of research, she says, has shown its impact on human health and the endocrine system. BPA binds to our own hormone receptors, so it may negatively impact the thyroid and brain. A study in 2015 was the first to identify a link between BPA and some children with autism, but the relationship was associative, not causative. Meanwhile, the Food and Drug Administration maintains that BPA is safe at the current levels occurring in food, based on its ongoing review of the available scientific evidence.
Michael Mooney, President of St. Louis-based Delta Genesis, a non-profit organization that treats children struggling with neurodevelopmental delays like autism, suspects a strong role for epigenetics, which refers to changes in how genes are expressed as a result of environmental influences, lifestyle behaviors, age, or disease states.
He believes some children are genetically predisposed to the disorder, and some unknown influence or combination of influences pushes them over the edge, triggering epigenetic changes that result in symptoms of autism.
For Stefania Sterling, it doesn't really matter how or why she had an autistic child. That's only one part of Charlie.
"It's not everything that makes Charlie," she said. "He's just like any other kid. He comes with happy moments. He comes with sad moments. Just like my other three kids."
Hacking Your Own Genes: A Recipe for Disaster
Employees of ODIN, a consumer genetic design and engineering company, working out of their Bay Area garage start-up lab in 2016.
Editor's Note: Our Big Moral Question this month is: "Where should we draw a line, if any, between the use of gene editing for the prevention and treatment of disease, and for cosmetic enhancement?" It is illegal in the U.S. to develop human trials for the latter, even though some people think it should be acceptable. The most outspoken supporter recently resorted to self-experimentation using CRISPR in his own makeshift lab. But critics argue that "biohackers" like him are recklessly courting harm. LeapsMag invited a leading intellectual from the Center for Genetics and Society to share her perspective.
"I want to democratize science," says biohacker extraordinaire Josiah Zayner.
This is certainly a worthy-sounding sentiment. And it is central to the ethos of biohacking, a term that's developed a bit of sprawl. Biohacking can mean non-profit community biology labs that promote "citizen science," or clever but not necessarily safe or innocuous garage-based experiments with computers and genetics, or efforts at biological self-optimization via techniques including cybernetic implants, drug supplements, and intermittent fasting.
They appear to have given little thought to whether curiosity should be bound in any way by care for social consequence.
Against that messy background, what should we make of Zayner? The thirty-something ex-NASA scientist, who describes himself as "a global leader in the BioHacker movement," put his interpretation of democracy on display last October during a CRISPR-yourself performance at a San Francisco biotech conference. In that episode, he dramatically jabbed himself with a long needle, injecting his left forearm with a home-made gene-editing concoction that he said would disrupt his myostatin genes and bulk up his muscles.
Zayner sees himself, and is seen by some fellow biohackers, as a rebel hero: an intrepid scientific adventurer willing to risk his own well-being in the tradition of self-experimentation, eager to push the boundaries of established science in the service of forging innovative modes of discovery, ready to stand up to those stodgy bureaucrats at the FDA in the name of biohacker freedom.
To others, including some in the biohacker community, he's a publicity-seeking stunt man, perhaps deluded by touches of toxic masculinity and techno-entrepreneurial ideology, peddling snake-oil with oozing ramifications.
Zayner is hardly coy about his goals being larger than Popeye-like muscles. "I want to live in a world where people are genetically modifying themselves," he told FastCompany. "I think this is, like, literally, a new era of human beings," he mused to CBS in November. "It's gonna create a whole new species of humans."
Nor does he deign to conceal his tactics. The webpage of the company he launched to sell DIY gene-editing kits (which is advised by celebrity geneticist George Church) says that Zayner is "constantly pushing the boundaries of Science outside traditional environments." He is more explicit when performing: "Yes I am a criminal. And my crime is that of curiosity," he said last August to a biohacker audience in Oakland, which according to Gizmodo erupted in applause.
Regrettably, Zayner, along with some other biohackers and their defenders in the mainstream scientific world, appear to have given little thought to whether curiosity should be bound in any way by care for social consequence.
In December, the FDA issued a brief statement warning against using DIY kits for self-administered gene editing.
Though what's most directly at risk in Zayner's self-enhancement hack is his own safety, his bad-boy celebrity status is likely to encourage emulation. A few weeks after his San Francisco performance, 27-year-old Tristan Roberts took to Facebook Live to give himself a DIY gene modification injection to keep his HIV infection in check, because he doesn't like taking the regular medications that prevent AIDS. Whatever it was that he put into his body was provided by a company that Gizmodo describes as a "mysterious biotech firm with transhumanist leanings."
Zayner doesn't outright provide DIY gene hacks to others. But among his company's offerings are a free DIY Human CRISPR Guide and a $20 CRISPR-Cas9 plasmid that targets the human myostatin gene – the one that Zayner said he was targeting to make his muscles grow. Presumably to fend off legal problems, the product page says: "This product is not injectable or meant for direct human use" – a label as toothless as the fine print on cigarette packages that breaks the news that smoking causes cancer.
Some scientists warn that Zayner's style of biohacking carries considerable dangers. Microbiologist Brian Hanley, himself a self-experimenter who now opposes "biohacking humans," focuses on the technical difficulty of purifying what's being injected. "Screwing up can kill you from endotoxin," he says. "If you get in trouble, call me. I will do my best to instruct the physician how to save your life….But I make no guarantees you will survive."
Hanley also commented on the likely effectiveness of Zayner's effort: "Either Josiah Zayner is ignorant or he is deliberately misleading people. What he suggests cannot work as advertised."
Ensuring the safety and effectiveness of medical drugs and devices is the mandate of the US Food and Drug Administration. In December, the agency issued a brief statement warning against using DIY kits for self-administered gene editing, and saying flat out that selling them is against the law.
The stem cell field provides an unfortunate model of what can go wrong.
Zayner is dismissive of the safety risks. He asks in a Buzzfeed article whether DIY CRISPR should be considered more harmful than smoking or chemotherapy, "legal and socially acceptable activities that damage your genes." This is a strange line of argument, given the decades-long battles with the tobacco industry to raise awareness about smoking's significant harms, and since the side effects of chemotherapy are typically not undertaken by choice.
But the implications of what Zayner, Roberts, and some of their fellow biohackers are promoting ripple well beyond direct harms to individuals. Their rhetoric and vision affect the larger project of biomedicine, and the fraught relationships among drug researchers, pharmaceutical companies, clinical trial subjects, patients, and the public. Writing in Scientific American, Eleanor Pauwels of the Wilson Center, who is sympathetic to biohacking, lists the down sides: "blurred boundaries between treatments and self-experimentation, peer pressure to participate in trials, exploitation of vulnerable individuals, lack of oversight concerning quality control and risk of harm, and more."
These prospects are germane to the current state of human gene editing. After decades of dashed hopes, including deaths of research subjects, "gene therapy" may now be close to deserving the promise in its name. But with safety and efficacy still being evaluated, it's especially crucial to be honest about limitations as well as possibilities.
The stem cell field provides an unfortunate model of what can go wrong. Fifteen years ago, scientists, patient advocates, and even politicians routinely indulged in wildly over-optimistic enthusiasm about the imminence of stem cell therapies. That binge of irresponsible promotion helped create the current situation of widespread stem cell fraud: hundreds of clinics in the US alone selling unproven treatments to unsuspecting and sometimes desperate patients. Many have had their wallets lightened; some have gone blind or developed strange tumors that doctors have never before seen. The FDA is scrambling to address this still-worsening situation.
Zayner-style biohacking and promotion may also impact the ongoing controversy about whether new gene editing tools should be used in human reproduction to pre-determine the traits of future children and generations. Much of the widespread opposition to "human germline modification" is grounded in concern that it would lead to a society in which real or purported genetic advantages, marketed by fertility clinics to affluent parents, would exacerbate our already shameful levels of inequality and discrimination.
With powerful new technologies increasingly shaping the world, there's a lot riding on our capacity to democratize science. But as a society we don't yet have much practice at it.
Yet Zayner is all for it. In an interview in The Guardian, he comments, "DNA defines what a species is, and I imagine it wouldn't be too long into the future when the human species almost becomes a new species because of these modifications." He notes in a blog post, "We want to grow as a species and maybe change as a species. Whether that is curing disease or immortality or mutant powers is up to you."
This brings us back to Zayner's claim that he is working to democratize science.
The conviction that gene editing involves social and political challenges, not just technical matters, has been voiced at all points on the spectrum of perspective and uncertainty. But Zayner says there's been enough talk. "I want people to stop arguing about whether it's okay to use CRISPR or not use CRISPR….It's too late: I already made the choice for you. Argument over. Let's get on with it now. Let's use this to help people. Or to give people purple skin." (Emphasis added, in case there's any doubt about Zayner's commitment to democracy.)
With powerful new technologies increasingly shaping the world, there's a lot riding on our capacity to democratize science. But as a society we don't yet have much practice at it. In fact, we're not very sure what it would look like. It would clearly mean, as Arizona State University political scientist David Guston puts it, "considering the societal outcomes of research at least as attentively as the scientific and technological outputs." It would need broad participation and demand hard work.
The involvement of serious citizen scientists in such efforts, biohackers included, could be a very good thing. But Zayner's contributions to date have not been helpful.
[Ed. Note: Check out Zayner's perspective: "Genetic Engineering for All: The Last Great Frontier of Human Freedom." Then follow LeapsMag on social media to share your opinion.]
Could Biologically Enhancing Our Morality Save Our Species?
A human head pictured with a red heart in the place of a brain.
As a species, we are prone to weaponizing. There is a famous anecdote from Wulf Schievenhovel, a German anthropologist who was working in the highlands of New Guinea studying a local tribe. One day, he offered two tribesmen a flight in an airplane. They duly accepted but showed up with two large stones. When he asked why, they told him that they wanted to drop them on a neighboring village. Ethologist Frans de Waal later remarked on this story that Schievenhovel had effectively "witnessed the invention of the bomb."
Today you don't have to be Putin or Kim Jong Un to pose an existential threat.
Modern technology has given us access to more than just rocks. In 2011, a Swedish man was arrested after attempting a nuclear fission in his kitchen. And in the inaugural issue of this magazine, my colleague Hank Greely raised a terrifying prospect:
"do-it-yourself hobbyists can use CRISPR [gene editing]… to change the genomes of whole species of living things – domestic or wild; animal, vegetable, or microbial – cheaply, easily, and before we even know it is happening."
In science fiction, it is typically governments that take over technologies and use them for evil. That risk is of course no fiction. It is an ongoing problem that we have addressed through institutions: democracies, constitutions, legal systems and international treaties, and groups working together as checks and balances. It isn't perfect, but it has worked (so far).
Today you don't have to be Putin or Kim Jong Un to pose an existential threat. We are rapidly acquiring the technological ability for individuals and groups not just to cause major harm, but to do so exactly as Hank said: "cheaply, easily, and before we even know it is happening."
How should we address this problem? Together with Ingmar Persson, a fellow philosophy professor at Gothenburg, Sweden, I have argued that while education, institutions and good policing are important, we may need to think more radically.
We could adapt our biology so that we can appreciate the suffering of foreign or future people in the same instinctive way we do our friends and neighbors.
We evolved, along with the New Guinea tribesmen, to care about our small group and to be suspicious of outsiders. We evolved to cooperate well within our group, at a size where we could keep an eye on free riders. And we evolved to have the ability, and occasionally the desire to harm others, but with a natural limit on the amount of harm we could do—at least before others could step in to prevent, punish or kill us.
Our limitations have also become apparent in another form of existential threat: resource depletion. Despite our best efforts at educating, nudging, and legislating on climate change, carbon dioxide emissions in 2017 are expected to come in at the highest ever following a predicted rise of 2 percent. Why? We aren't good at cooperating in larger groups where freeriding is not easily spotted. We also deal with problems in order of urgency. A problem close by is much more significant to us than a problem in the future. That's why even if we accept there is a choice between economic recession now or natural disasters and potential famine in the future, we choose to carry on drilling for oil. And if the disasters and famine are present day, but geographically distant, we still choose to carry on drilling.
So what is our radical solution? We propose that there is a need for what we call moral bioenhancement. That is, for seeking a biological intervention that can help us overcome our evolved moral limitations. For example, adapting our biology so that we can appreciate the suffering of foreign or future people in the same instinctive way we do our friends and neighbors. Or, in the case of individuals, in addressing the problem of psychopathy from a biological perspective.
There is no reason in principle why humans could not be genetically modified...to make them kinder, happier, more conscientious, altruistic and just.
We have been dramatically successful at modifying various moral characteristics of non-human animals. Over ten thousand years or so, we have turned wolves into dogs by selective breeding, and those dogs into breeds with behavioural as well as physical characteristics: certain breeds can be faithful, hard working, good tempered and intelligent (or the opposite). Scientists have manipulated the expression of genes in prairie voles to cause them to form a mate bond more quickly, and in monkeys to make them work harder. There is no reason in principle why humans could not be genetically modified using gene editing, or their brains modified in other ways, to make them kinder, happier, more conscientious, altruistic and just.
One objection is that this is a pipe dream: even if it is acceptable to do this, it is so unlikely to be achievable, it is not worth pursuing. However, research has shown that we are already morally modified. This is widely accepted when it comes to negative effects. For example, we all know that alcohol can lead people to aggressive or other destructive behaviours that they would not have countenanced sober. In a 2008 case, a retired UK teacher was cleared of child pornography charges after he successfully argued his behaviour was caused by a drug prescribed for his Parkinson's disease. There is also evidence that we can be morally modified in a more positive direction. For example, SSRIs like Prozac, a class of drugs widely used to treat depression, have been shown to act on healthy volunteers to make them more cooperative and less critical.
Another objection is that we need the negative aspects of our human character. We need people who can fight wars. We need to be able to blot out the suffering of the wider world: to experience it as we would if it applied to our nearest and dearest would be unbearable. This might be so. If aggressiveness and denial, or strong bonding to small communities, are important traits, it is important that we understand how, and to what degree, they should be controlled. It is unlikely that nature has dished out exactly the right levels of all morally relevant characteristics on an individual or population level. We don't claim to have all the answers to what characteristics we need to enhance, and what characteristics we need to diminish. But we see no reason to believe that the status quo is the optimum.
We haven't argued that we should go blindly in now with half-baked moral enhancers, or that we should forget about moral education, or legal solutions. Evolution has a built-in response to existential threats through adaptation. But adaptation takes generations and can't deal with threats that take out a whole population. Some threats are too important —and too urgent—to be left to chance.