Can Genetic Testing Help Shed Light on the Autism Epidemic?
Autism cases are still on the rise, and scientists don't know why. In April, the Centers for Disease Control (CDC) reported that rates of autism had increased once again, now at an estimated 1 in 59 children up from 1 in 68 just two years ago. Rates have been climbing steadily since 2007 when the CDC initially estimated that 1 in 150 children were on the autism spectrum.
Some clinicians are concerned that the creeping expansion of autism is causing the diagnosis to lose its meaning.
The standard explanation for this increase has been the expansion of the definition of autism to include milder forms like Asperger's, as well as a heightened awareness of the condition that has improved screening efforts. For example, the most recent jump is attributed to children in minority communities being diagnosed who might have previously gone under the radar. In addition, more federally funded resources are available to children with autism than other types of developmental disorders, which may prompt families or physicians to push harder for a diagnosis.
Some clinicians are concerned that the creeping expansion of autism is causing the diagnosis to lose its meaning. William Graf, a pediatric neurologist at Connecticut Children's Medical Center, says that when a nurse tells him that a new patient has a history of autism, the term is no longer a useful description. "Even though I know this topic extremely well, I cannot picture the child anymore," he says. "Use the words mild, moderate, or severe. Just give me a couple more clues, because when you say autism today, I have no idea what people are talking about anymore."
Genetic testing has emerged as one potential way to remedy the overly broad label by narrowing down a heterogeneous diagnosis to a specific genetic disorder. According to Suma Shankar, a medical geneticist at the University of California, Davis, up to 60 percent of autism cases could be attributed to underlying genetic causes. Common examples include Fragile X Syndrome or Rett Syndrome—neurodevelopmental disorders that are caused by mutations in individual genes and are behaviorally classified as autism.
With more than 500 different mutations associated with autism, very few additional diagnoses provide meaningful information.
Having a genetic diagnosis in addition to an autism diagnosis can help families in several ways, says Shankar. Knowing the genetic origin can alert families to other potential health problems that are linked to the mutation, such as heart defects or problems with the immune system. It may also help clinicians provide more targeted behavioral therapies and could one day lead to the development of drug treatments for underlying neurochemical abnormalities. "It will pave the way to begin to tease out treatments," Shankar says.
When a doctor diagnoses a child as having a specific genetic condition, the label of autism is still kept because it is more well-known and gives the child access to more state-funded resources. Children can thus be diagnosed with multiple conditions: autism spectrum disorder and their specific gene mutation. However, with more than 500 different mutations associated with autism, very few additional diagnoses provide meaningful information. What's more, the presence or absence of a mutation doesn't necessarily indicate whether the child is on the mild or severe end of the autism spectrum.
Because of this, Graf doubts that genetic classifications are really that useful. He tells the story of a boy with epilepsy and severe intellectual disabilities who was diagnosed with autism as a young child. Years later, Graf ordered genetic testing for the boy and discovered that he had a mutation in the gene SYNGAP1. However, this knowledge didn't change the boy's autism status. "That diagnosis [SYNGAP1] turns out to be very specific for him, but it will never be a household name. Biologically it's good to know, and now it's all over his chart. But on a societal level he still needs this catch-all label [of autism]," Graf says.
"It gives some information, but to what degree does that change treatment or prognosis?"
Jennifer Singh, a sociologist at Georgia Tech who wrote the book Multiple Autisms: Spectrums of Advocacy and Genomic Science, agrees. "I don't know that the knowledge gained from just having a gene that's linked to autism," is that beneficial, she says. "It gives some information, but to what degree does that change treatment or prognosis? Because at the end of the day you have to address the issues that are at hand, whatever they might be."
As more children are diagnosed with autism, knowledge of the underlying genetic mutation causing the condition could help families better understand the diagnosis and anticipate their child's developmental trajectory. However, for the vast majority, an additional label provides little clarity or consolation.
Instead of spending money on genetic screens, Singh thinks the resources would be better used on additional services for people who don't have access to behavioral, speech, or occupational therapy. "Things that are really going to matter for this child in their future," she says.
Got a Virus? Its Name Matters More Than You Think
It's a familiar scenario: You show up at the doctor feeling miserable—sneezing, coughing, lethargic. We've all been there. And we've all been told the same answer: we're suffering from "a virus."
Failing to establish a specific microbial cause undermines the health of individual patients—and potentially the public at large.
Some patients may be satisfied with that diagnosis, others may be frustrated, and still others may demand antibiotic treatment for a bacterial infection that is usually not even present. As an infectious disease doctor who specializes in pandemic preparedness, I detest using the catch-all "virus" diagnosis for a range of symptoms from common colds to life-threatening pneumonias to unexplained fevers. Failing to establish a specific microbial cause undermines the health of individual patients—and potentially the public at large.
Confirming a specific diagnosis to determine which virus is behind those nasty symptoms is not just an academic exercise. The benefits are plentiful. Patients can forego antibiotic treatment, possibly benefit from antiviral treatment, understand their illness, and be given a prognosis. Additionally, if hospitalized, patients with certain viral infections require specific types of precautions so as not to spread the virus within the hospital.
Another largely undervalued benefit of such an approach is that it allows experts to begin assembling an arsenal of tools that might stave off a global health catastrophe. With severe pandemics, such as the 1918 influenza pandemic that killed 50 to 100 million people, it can be challenging to predict which of the myriad microbial species (bacteria, viruses, fungi, parasites, prions) will be the most likely cause. Many different approaches to prediction exist, but there is a general lack of rigorous analysis about what it takes for any microorganism to reach the pantheon of pandemic pathogens. My colleagues and I at the Johns Hopkins Center for Health Security recently developed a new framework to understand the characteristics of pandemic pathogens.
One of our major conclusions is that the most likely pandemic pathogen will be viral and spread through respiratory means. Viruses rise to the top of the list because, when compared to other types of infectious agents, they have several features that confer pandemic potential: they mutate a lot, the speed of infection is rapid, and there are no broad-spectrum antivirals akin to broad-spectrum antibacterial agents. Contagion through breathing, coughing, and sneezing is likely because it is much more difficult for standard public health measures to extinguish respiratory spread agents compared to other routes of transmission like food, body fluids, or mosquitoes.
With this information, physicians and scientists can begin taking actions to prevent spread of the infection by developing vaccines, testing antiviral compounds, and making diagnostic tests for concerning viruses.
Many of the viral families that could pose a pandemic threat are very common causes of upper respiratory infections like influenza, the common cold, and bronchitis. These viruses cause a wide range of illnesses from mild coughs to serious pneumonias. Indeed, the 2009 H1N1 influenza pandemic virus was discovered in San Diego in a child with very mild illness in whom viral diagnostic testing was pursued. This event highlights the fact that such diseases are not only found in exotic locations in the developing world, but could appear anywhere.
Understanding the patterns of respiratory virus infections -- how frequent they are, which strains are predominating, changes in severity of disease, expanding geographic range -- may provide a glimpse into the first forays of a new human virus or an alert to changing behavior from a well-known virus. With this information, physicians and scientists can begin taking actions to prevent spread of the infection by developing vaccines, testing antiviral compounds, and making diagnostic tests for concerning viruses. Additionally, alerts to healthcare providers will provide greater situational awareness of the patterns of infection.
So, the next time you are given a wastebasket diagnosis of "viral syndrome," push your doctor a little harder. In 2018, we have countless diagnostic tests for viral infections available, many at the point-of-care, that too few physicians use. Not only will you be more satisfied with a real diagnosis, you may be spared an unnecessary course of antibiotics. You can also rest assured that having a name for your virus will help epidemiologists doing a very important job. While we have not yet technologically achieved the famed Tricorder of Star Trek fame that diagnoses everything with a sweep of the hand, using the tools we do have could be one of the keys to detecting the next pandemic virus early enough to intervene.
Dr. Adalja is focused on emerging infectious disease, pandemic preparedness, and biosecurity. He has served on US government panels tasked with developing guidelines for the treatment of plague, botulism, and anthrax in mass casualty settings and the system of care for infectious disease emergencies, and as an external advisor to the New York City Health and Hospital Emergency Management Highly Infectious Disease training program, as well as on a FEMA working group on nuclear disaster recovery. Dr. Adalja is an Associate Editor of the journal Health Security. He was a coeditor of the volume Global Catastrophic Biological Risks, a contributing author for the Handbook of Bioterrorism and Disaster Medicine, the Emergency Medicine CorePendium, Clinical Microbiology Made Ridiculously Simple, UpToDate's section on biological terrorism, and a NATO volume on bioterrorism. He has also published in such journals as the New England Journal of Medicine, the Journal of Infectious Diseases, Clinical Infectious Diseases, Emerging Infectious Diseases, and the Annals of Emergency Medicine. He is a board-certified physician in internal medicine, emergency medicine, infectious diseases, and critical care medicine. Follow him on Twitter: @AmeshAA
This past March, headlines suddenly flooded the Internet about a startup company called Nectome. Founded by two graduates of the Massachusetts Institute of Technology, the new company was charging people $10,000 to join a waiting list to have their brains embalmed, down to the last neuron, using an award-winning chemical compound.
While the lay public presumably burnt their wills and grew ever more excited about the end of humanity's quest for immortality, neurologists let out a collective sigh.
Essentially, participants' brains would turn to a substance like glass and remain in a state of near-perfect preservation indefinitely. "If memories can truly be preserved by a sufficiently good brain banking technique," Nectome's website explains, "we believe that within the century it could become feasible to digitize your preserved brain and use that information to recreate your mind." But as with most Faustian bargains, Nectome's proposition came with a serious caveat -- death.
That's right, in order for Nectome's process to properly preserve your connectome, the comprehensive map of the brain's neural connections, you must be alive (and under anesthesia) while the fluid is injected. This way, the company postulates, when the science advances enough to read and extract your memories someday, your vitrified brain will still contain your perfectly preserved essence--which can then be digitally recreated as a computer simulation.
Almost immediately this story gained buzz with punchy headlines: "Startup wants to upload your brain to the cloud, but has to kill you to do it," "San Junipero is real: Nectome wants to upload your brain," and "New tech firm promises eternal life, but you have to die."
While the lay public presumably burnt their wills and grew ever more excited about the end of humanity's quest for immortality, neurologists let out a collective sigh -- hype had struck the scientific community once again.
The truth about Nectome is that its claims are highly speculative and no hard science exists to suggest that our connectome is the key to our 'being,' nor that it can ever be digitally revived. "We haven't come even close to understanding even the most basic types of functioning in the brain," says neuroscientist Alex Fox, who was educated at the University of Queensland in Australia. "Memory storage in the brain is only a theoretical concept [and] there are some seriously huge gaps in our knowledge base that stand in the way of testing [the connectome] theory."
After the Nectome story broke, Harvard computational neuroscientist Sam Gershman tweeted out:
"Didn't anyone tell them that we've known the C Elegans (a microscopic worm) connectome for over a decade but haven't figured out how to reconstruct all of their memories? And that's only 7000 synapses compared to the trillions of synapses in the human brain!"
Hype can come from researchers themselves, who are under an enormous amount of pressure to publish original work and maintain funding.
How media coverage of Nectome went from an initial fastidiously researched article in the MIT Technology Review by veteran science journalist Antonio Regalado to the click-bait frenzy it became is a prime example of the 'science hype' phenomenon. According to Adam Auch, who holds a doctorate in philosophy from Dalhousie University in Nova Scotia, Canada, "Hype is a feature of all stages of the scientific dissemination process, from the initial circulation of preliminary findings within particular communities of scientists, to the process by which such findings come to be published in peer-reviewed journals, to the subsequent uptake these findings receive from the non-specialist press and the general public."
In the case of Nectome, hype was present from the word go. Riding the high of several major wins, including having raised over one million dollars in funding and partnering with well-known MIT neurologist Edward Boyden, Nectome founders Michael McCanna and Robert McIntyre launched their website on March 1, 2018. Just one month prior, they were able to purchase and preserve a newly deceased corpse in Portland, Oregon, showing that vitrifixation, their method of chemical preservation, could be used on a human specimen. It had previously won an award for preserving every synaptic structure on a rabbit brain.
The Nectome mission statement, found on its website, is laced with saccharine language that skirts the unproven nature of the procedure the company is peddling for big bucks: "Our mission is to preserve your brain well enough to keep all its memories intact: from that great chapter of your favorite book to the feeling of cold winter air, baking an apple pie, or having dinner with your friends and family."
This rhetoric is an example of hype that can come from researchers themselves, who are under an enormous amount of pressure to publish original work and maintain funding. As a result, there is a constant push to present science as "groundbreaking" when really, as is apparently the case with Nectome, it is only a small piece in a much larger effort.
Calling out the audacity of Nectome's posited future, neuroscientist Gershman commented to another publication, "The important question is whether the connectome is sufficient for memory: Can I reconstruct all memories knowing only the connections between neurons? The answer is almost certainly no, given our knowledge about how memories are stored (itself a controversial topic)."
The former home page of Nectome's website, which has now been replaced by a statement titled, "Response to recent press."
Furthermore, universities like MIT, who entered into a subcontract with Nectome, are under pressure to seek funding through partnerships with industry as a result of the Bayh-Dole Act of 1980. Also known as the Patent and Trademark Law Amendments Act, this piece of legislation allows universities to commercialize inventions developed under federally funded research programs, like Nectome's method of preserving brains, formally called Aldehyde-Stabilized Cryopreservation.
"[Universities use] every incentive now to talk about innovation," explains Dr. Ivan Oransky, president of the Association of Health Care Journalists and co-founder of retractionwatch.com, a blog that catalogues errors and fraud in published research. "Innovation to me is often a fancy word for hype. The role of journalists should not be to glorify what universities [say, but to] tell the closest version of the truth they can."
In this case, a combination of the hyperbolic press, combined with some impressively researched expose pieces, led MIT to cut its ties with Nectome on April 2nd, 2018, just two weeks after the news of their company broke.
The solution to the dangers of hype, experts say, is a more scientifically literate public—and less clickbait-driven journalism.
Because of its multi-layered nature, science hype carries several disturbing consequences. For one, exaggerated coverage of a discovery could mislead the public by giving them false hope or unfounded worry. And media hype can contribute to a general mistrust of science. In these instances, people might, as Auch puts it, "fall back on previously held beliefs, evocative narratives, or comforting biases instead of well-justified scientific evidence."
All of this is especially dangerous in today's 'fake news' era, when companies or political parties sow public confusion for their own benefit, such as with global warming. In the case of Nectome, the danger is that people might opt to end their lives based off a lacking scientific theory. In fact, the company is hoping to enlist terminal patients in California, where doctor-assisted suicide is legal. And 25 people have paid the $10,000 to join Nectome's waiting list, including Sam Altman, president of the famed startup accelerator Y Combinator. Nectome now has offered to refund the money.
Founders McCanna and McIntyre did not return repeated requests for comment for this article. A new statement on their website begins: "Vitrifixation today is a powerful research tool, but needs more research and development before anyone considers applying it in a context other than research."
The solution to the dangers of hype, experts say, is a more scientifically literate public—and less clickbait-driven journalism. Until then, it seems that companies like Nectome will continue to enjoy at least 15 minutes of fame.