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.
The Ethics of Navigating Teen Gender Transitions
At first, Miriam Zachariah's teenage nephew Theo, who was born female, came out as gay. But he "presented as very gender fluid," she says, which suggested that he hadn't made "a clear choice one way or another."
Families, physicians, and psychologists have pondered whether it's better, neutral, or worse to postpone gender transitions until adulthood.
Zachariah decided to ask her nephew, "Do you think you might be trans?" While he answered "no," the question "broke something open for him," she recalls.
A month later, at age 13, he began identifying as trans. And at 14 1/2, he started undergoing gender transition with an endocrine-blocking injection. More recently, at age 16, he added testosterone injections, and soon he won't need the endocrine blocker any longer.
"His voice is deepening, and his muscle mass is growing," says Zachariah, a principal of two elementary schools in Toronto who became her nephew's legal guardian while he was starting to transition.
There are many medical and bioethical aspects associated with the transition to one's self-identified gender, especially when the process involves children and adolescents. Families, physicians, and psychologists have pondered whether it's better, neutral, or worse to postpone the transition until adulthood, while remaining cognizant of the potential consequences to puberty suppression with cross-sex hormones and the irreversibility of transgender surgeries.
Studies have found a higher prevalence of mental health issues among transgender and gender nonconforming youth, particularly if they are unable to express themselves in the self-identified gender. Research also has shown that transgender adults in the process of transitioning initially experienced worse mental health problems than their adolescent counterparts.
The Endocrine Society, a professional medical organization that provides recommendations for clinical practice, stipulates in its guidelines that the diagnosis of gender identity be limited to qualified mental health professionals for those under age 18. This is important because children are still evolving in their thought processes and capacity to articulate themselves, says endocrinologist Joshua Safer, inaugural executive director of the Center for Transgender Medicine and Surgery at the Icahn School of Medicine at Mount Sinai in New York.
A transition can begin safely in gradations, by allowing young children to experiment with haircuts and clothes of either gender before puberty. "If it just ends up being a stage of life, we haven't done anything permanent," says Safer, who is president of the United States Professional Association for Transgender Health as well as steering committee co-chair of TransNet, the international transgender research consortium.
After changes in appearance, the next step would be to try puberty blockers. Also used to halt precocious puberty, the injections are "a reasonably established intervention" for transgender youth, although there are some concerns that the drugs could interfere with bone health in the future, he says.
From a mental health standpoint, "hormones for youth who qualify for them have offered a tremendous boost in well-being and also a reduction in anxiety, depression, and suicidality that often plague transgender youth when they experience their bodies as totally discordant with their self-knowledge of their authentic gender," says psychologist Diane Ehrensaft, director of mental health in the Child and Adolescent Gender Center at Benioff Children's Hospital of the University of California at San Francisco.
Many of these youth have either known about or have been living in their authentic gender since early childhood; others discovered their true identities in adolescence, often with the onset of puberty, says Ehrensaft, associate professor of pediatrics. The effects of gender-affirming hormone treatments are at least partially reversible, she adds, whereas surgical procedures are irreversible. Regardless of reversibility, best practices include careful consideration of all interventions to ensure they are in a youth's best interests in promoting gender health and general well-being.
When a child exhibits signs of gender dysphoria, parents and guardians should at a minimum take these feelings seriously.
In determining readiness for a transgender operation, an assessment of maturity is as important as chronological age, says Loren Schechter, plastic surgeon and director of the Center for Gender Confirmation Surgery at Weiss Memorial Hospital in Chicago. With the consent of a parent or guardian, he commonly performs mastectomies on adolescents at age 17 and sometimes earlier, based on the clinical circumstances and along with a multidisciplinary team that includes a primary care provider and a mental health professional.
"Typically, before surgery, people have had the opportunity and time to consider their options," Schechter says, observing that "the incidence of regret or changing one's mind is extremely low." Others may opt to transition socially but not surgically. "We recognize that gender is not binary," he explains. Some individuals may not "discreetly fit into male or female" in how they perceive themselves.
When a child exhibits signs of gender dysphoria, parents and guardians should at a minimum take these feelings seriously, not dismiss them. They may want to enlist the assistance of a gender identity clinic to address the social environment and guide the child in exploring activities with the self-identified gender, says Kelly McBride Folkers, research associate in the Division of Medical Ethics at New York University School of Medicine.
At one end of the spectrum, some parents and guardians are overzealous in supporting their child's gender-identity pursuits while the youngster is still in an early phase of decision-making. On the flipside, other parents and guardians are not at all supportive, leaving the child at risk for long-term psychological effects, says Folkers, who is also associate director of the High School Bioethics Project at NYU, an educational program that aids teachers and students in examining ethical and conceptual concepts across various areas, one of which is gender.
"It's important to help children navigate through this process early, so that they have all of the social and familial support they need if and when they choose to seek medical options for gender affirmation later," she says.
There are various reasons why children and adolescents want to explore the opposite gender when they reach puberty. "It's a small percentage who will persist and insist and be consistent with that opposite gender identity," says Nicole Mihalopoulos, adolescent medicine physician and associate professor of pediatrics at the University of Utah School of Medicine in Salt Lake City.
Turning to a social work support system can help bring clarity for teens, parents, and guardians.
For those youth, it's appropriate to start the conversation about a medication to block puberty, but without actually promoting a hormonal transition to the opposite gender, in order for the child to further explore living as the opposite gender. "Children need to start at puberty because we need to know that their bodies are physiologically normal," Mihalopoulos says.
A lack of breast development in girls or a lack of testicular development in boys could point to an abnormality in the hypothalamus, pituitary gland, or ovaries/testicles. "That needs to be identified and corrected first," she explains, "before I would say, 'Let's start on the medical transition path of the alternate gender.' "
For parents and guardians, says Theo Zachariah's aunt Miriam, it's very tempting to misinterpret a child's struggling attempts to articulate being trans as an adolescent identity crisis. That's when turning to a social work support system can bring clarity. A youth mental health agency with experience in trans issues made a positive impact on Theo's family through one-on-one counseling and in groups for teens and parents.
"The dialogue they were able to engage in with my nephew, his mom and us," she says, was very instrumental "in helping us all figure out what to do and how to navigate the change."
Can Cultured Meat Save the Planet?
In September, California governor Jerry Brown signed a bill mandating that by 2045, all of California's electricity will come from clean power sources. Technological breakthroughs in producing electricity from sun and wind, as well as lowering the cost of battery storage, have played a major role in persuading Californian legislators that this goal is realistic.
Even if the world were to move to an entirely clean power supply, one major source of greenhouse gas emissions would continue to grow: meat.
James Robo, the CEO of the Fortune 200 company NextEra Energy, has predicted that by the early 2020s, electricity from solar farms and giant wind turbines will be cheaper than the operating costs of coal-fired power plants, even when the cost of storage is included.
Can we therefore all breathe a sigh of relief, because technology will save us from catastrophic climate change? Not yet. Even if the world were to move to an entirely clean power supply, and use that clean power to charge up an all-electric fleet of cars, buses and trucks, one major source of greenhouse gas emissions would continue to grow: meat.
The livestock industry now accounts for about 15 percent of global greenhouse gas emissions, roughly the same as the emissions from the tailpipes of all the world's vehicles. But whereas vehicle emissions can be expected to decline as hybrids and electric vehicles proliferate, global meat consumption is forecast to be 76 percent greater in 2050 than it has been in recent years. Most of that growth will come from Asia, especially China, where increasing prosperity has led to an increasing demand for meat.
Changing Climate, Changing Diets, a report from the London-based Royal Institute of International Affairs, indicates the threat posed by meat production. At the UN climate change conference held in Cancun in 2010, the participating countries agreed that to allow global temperatures to rise more than 2°C above pre-industrial levels would be to run an unacceptable risk of catastrophe. Beyond that limit, feedback loops will take effect, causing still more warming. For example, the thawing Siberian permafrost will release large quantities of methane, causing yet more warming and releasing yet more methane. Methane is a greenhouse gas that, ton for ton, warms the planet 30 times as much as carbon dioxide.
The quantity of greenhouse gases we can put into the atmosphere between now and mid-century without heating up the planet beyond 2°C – known as the "carbon budget" -- is shrinking steadily. The growing demand for meat means, however, that emissions from the livestock industry will continue to rise, and will absorb an increasing share of this remaining carbon budget. This will, according to Changing Climate, Changing Diets, make it "extremely difficult" to limit the temperature rise to 2°C.
One reason why eating meat produces more greenhouse gases than getting the same food value from plants is that we use fossil fuels to grow grains and soybeans and feed them to animals. The animals use most of the energy in the plant food for themselves, moving, breathing, and keeping their bodies warm. That leaves only a small fraction for us to eat, and so we have to grow several times the quantity of grains and soybeans that we would need if we ate plant foods ourselves. The other important factor is the methane produced by ruminants – mainly cattle and sheep – as part of their digestive process. Surprisingly, that makes grass-fed beef even worse for our climate than beef from animals fattened in a feedlot. Cattle fed on grass put on weight more slowly than cattle fed on corn and soybeans, and therefore do burp and fart more methane, per kilogram of flesh they produce.
Richard Branson has suggested that in 30 years, we will look back on the present era and be shocked that we killed animals en masse for food.
If technology can give us clean power, can it also give us clean meat? That term is already in use, by advocates of growing meat at the cellular level. They use it, not to make the parallel with clean energy, but to emphasize that meat from live animals is dirty, because live animals shit. Bacteria from the animals' guts and shit often contaminates the meat. With meat cultured from cells grown in a bioreactor, there is no live animal, no shit, and no bacteria from a digestive system to get mixed into the meat. There is also no methane. Nor is there a living animal to keep warm, move around, or grow body parts that we do not eat. Hence producing meat in this way would be much more efficient, and much cleaner, in the environmental sense, than producing meat from animals.
There are now many startups working on bringing clean meat to market. Plant-based products that have the texture and taste of meat, like the "Impossible Burger" and the "Beyond Burger" are already available in restaurants and supermarkets. Clean hamburger meat, fish, dairy, and other animal products are all being produced without raising and slaughtering a living animal. The price is not yet competitive with animal products, but it is coming down rapidly. Just this week, leading officials from the Food and Drug Administration and the U.S. Department of Agriculture have been meeting to discuss how to regulate the expected production and sale of meat produced by this method.
When Kodak, which once dominated the sale and processing of photographic film, decided to treat digital photography as a threat rather than an opportunity, it signed its own death warrant. Tyson Foods and Cargill, two of the world's biggest meat producers, are not making the same mistake. They are investing in companies seeking to produce meat without raising animals. Justin Whitmore, Tyson's executive vice-president, said, "We don't want to be disrupted. We want to be part of the disruption."
That's a brave stance for a company that has made its fortune from raising and killing tens of billions of animals, but it is also an acknowledgement that when new technologies create products that people want, they cannot be resisted. Richard Branson, who has invested in the biotech company Memphis Meats, has suggested that in 30 years, we will look back on the present era and be shocked that we killed animals en masse for food. If that happens, technology will have made possible the greatest ethical step forward in the history of our species, saving the planet and eliminating the vast quantity of suffering that industrial farming is now inflicting on animals.