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.
Shoot for the Moon: Its Surface Contains a Pot of Gold
Here's a riddle: What do the Moon, nuclear weapons, clean energy of the future, terrorism, and lung disease all have in common?
One goal of India's upcoming space probe is to locate deposits of helium-3 that are worth trillions of dollars.
The answer is helium-3, a gas that's extremely rare on Earth but 100 million times more abundant on the Moon. This past October, the Lockheed Martin corporation announced a concept for a lunar landing craft that may return humans to the Moon in the coming decade, and yesterday China successfully landed the Change-4 probe on the far side of the Moon. Landing inside the Moon's deepest crater, the Chinese achieved a first in space exploration history.
Meanwhile, later this month, India's Chandrayaan-2 space probe will also land on the lunar surface. One of its goals is to locate deposits of helium-3 that are worth trillions of dollars, because it could be a fuel for nuclear fusion energy to generate electricity or propel a rocket.
The standard way that nuclear engineers are trying to achieve sustainable fusion uses fuels that are more plentiful on Earth: deuterium and tritium. But MIT researchers have found that adding small amounts of helium-3 to the mix could make it much more efficient, and thus a viable energy source much sooner that once thought.
Even if fusion is proven practical tomorrow, any kind of nuclear energy involves long waits for power plant construction measured in decades. However, mining helium-3 could be useful now, because of its non-energy applications. A major one is its ability to detect neutrons coming from plutonium that could be used in terrorist attacks. Here's how it works: a small amount of helium-3 is contained within a forensic instrument. When a neutron hits an atom of helium-3, the reaction produces tritium, a proton, and an electrical charge, alerting investigators to the possibility that plutonium is nearby.
Ironically, as global concern about a potential for hidden nuclear material increased in the early 2000s, so did the supply of helium-3 on Earth. That's because helium-3 comes from the decay of tritium, used in thermonuclear warheads (H-bombs). Thousands of such weapons have been dismantled from U.S. and Russian arsenals, making helium-3 available for plutonium detection, research, and other applications--including in the world of healthcare.
Helium-3 can help doctors diagnose lung diseases, since it enables imaging of the lungs in real time.
Helium-3 dramatically improves the ability of doctors to image the lungs in a range of diseases including asthma, chronic obstructive pulmonary disease and emphysema, cystic fibrosis, and bronchopulmonary dysplasia, which happens particularly in premature infants. Specifically, helium-3 is useful in magnetic resonance imaging (MRI), a procedure that creates images from within the body for diagnostic purposes.
But while a standard MRI allows doctors to visualize parts of the body like the heart or brain, it's useless for seeing the lungs. Because lungs are filled with air, which is much less dense than water or fat, effectively no signals are produced that would enable imaging.
To compensate for this problem, a patient can inhale gas that is hyperpolarized –meaning enhanced with special procedures so that the magnetic resonance signals from the lungs are finally readable. This gas is safe to breathe when mixed with enough oxygen to support life. Helium-3 is one such gas that can be hyperpolarized; since it produces such a strong signal, the MRI can literally see the air inside the lungs and in all of the airways, revealing intricate details of the bronchopulmonary tree. And it can do this in real time
The capability to show anatomic details of the lungs and airways, and the ability to display functional imaging as a patient breathes, makes helium-3 MRI far better than the standard method of testing lung function. Called spirometry, this method tells physicians how the lungs function overall, but does not home in on particular areas that may be causing a problem. Plus, spirometry requires patients to follow instructions and hold their breath, so it is not great for testing young children with pulmonary disease.
In recent years, the cost of helium-3 on Earth has skyrocketed.
Over the past several years, researchers have been developing MRI for lung testing using other hyperpolarized gases. The main alternative to helium-3 is xenon-129. Over the years, researchers have learned to overcome certain disadvantages of the latter, such as its potential to put patients to sleep. Since helium-3 provides the strongest signal, though, it is still the best gas for MRI studies in many lung conditions.
But the supply of helium-3 on Earth has been decreasing in recent years, due to the declining rate of dismantling of warheads, just as the Department of Homeland Security has required more and more of the gas for neutron detection. As a result, the cost of the gas has skyrocketed. Less is available now for medical uses – unless, of course, we begin mining it on the moon.
The question is: Are the benefits worth the 239,000-mile trip?
Should Organ Donors Be Paid?
Deanna Santana had assumed that people on organ transplant lists received matches. She didn't know some died while waiting. But in May 2011, after her 17-year-old son, Scott, was killed in a car accident, she learned what a precious gift organ and tissue donation can be.
"I would estimate it cost our family about $4,000 for me to donate a kidney to a stranger."
His heart, lungs, kidneys, liver and pancreas saved five people. His corneas enabled two others to see. And his bones, connective tissues and veins helped 73 individuals.
The donation's impact had a profound effect on his mother as well. In September 2016, she agreed to donate a kidney in a paired exchange of four people making the same sacrifice for four compatible strangers.
She gave up two weeks' worth of paid vacation to recuperate and covered lodging costs for loved ones during her transplant. Eventually, she qualified for state disability for part of her leave, but the compensation was less than her salary as public education and relations manager at Sierra Donor Services, an organ procurement organization in West Sacramento, California.
"I would estimate it cost our family about $4,000 for me to donate a kidney to a stranger," says Santana, 51. Despite the monetary hardship, she "would do it again in a heartbeat."
While some contend it's exploitative to entice organ donors and their families with compensation, others maintain they should be rewarded for extending their generosity while risking complications and recovering from donation surgery. But many agree on one point: The focus should be less on paying donors and more on removing financial barriers that may discourage interested prospects from doing a good deed.
"There's significant potential risk associated with donating a kidney, some of which we're continuing to learn," says transplant surgeon Matthew Cooper, a board member of the National Kidney Foundation and co-chair of its Transplant Task Force.
Although most kidneys are removed laparoscopically, reducing hospitalization and recuperation time, complications can occur. The risks include wound and urinary tract infections, pneumonia, blood clots, injury to local nerves causing decreased sensation in the hip or thigh, acute blood loss requiring transfusion and even death, Cooper says.
"We think that donation is a cost-neutral opportunity. It, in fact, is not."
Meanwhile, from a financial standpoint, estimates have found it costs a kidney donor in the United States an average of $3,000 to navigate the entire transplant process, which may include time off from work, travel to and from the hospital, accommodations, food and child care expenses.
"We think that donation is a cost-neutral opportunity. It, in fact, is not," says Cooper, who is also Director of Kidney and Pancreas Transplantation at MedStar Georgetown Transplant Institute in Washington, D.C.
The National Organ Transplant Act of 1984 makes it illegal to sell human organs but did not prohibit payment for the donation of human plasma, sperm and egg cells.
Unlike plasma, sperm and eggs cells—which are "renewable resources"—a kidney is irreplaceable, says John J. Friedewald, a nephrologist who is medical director of kidney transplantation at Northwestern Memorial Hospital in Chicago.
Offering some sort of incentives could lessen the overall burden on donors while benefiting many more potential recipients. "We can eliminate the people waiting on the list and dying, at least for kidneys," Friedewald says.
On the other hand, incentives may influence an individual to the point that the donation is made purely for monetary gain. "It's a delicate balance," he explains, "because so much of the transplant system has been built on altruism."
That's where doing away with the "disincentives" comes into the equation. Compensating donors for the costs they endure would be a reasonable compromise, Friedewald says.
Depending on the state, living donors may deduct up to $10,000 from their adjusted gross income under the Organ Donation Tax Deduction Act for the year in which the transplantation occurs. "Human organ" applies to all or part of a liver, pancreas, kidney, intestine, lung or bone marrow. The subtracted modification may be claimed for only unreimbursed travel and lodging expenses and lost wages.
For some or many donors, the tax credit doesn't go far enough in offsetting their losses, but they often take it in stride, says Chaya Lipschutz, a Brooklyn, N.Y.-based matchmaker for donors and recipients, who launched the website KidneyMitzvah.com in 2009.
Seeking compensation for lost wages "is extremely rare" in her experience. "In all the years of doing this," she recalls, "I only had two people who donated a kidney who needed to get paid for lost wages." She finds it "pretty amazing that mostly all who contact don't ask."
Lipschutz, an Orthodox Jew, has walked in a donor's shoes. In September 2005, at age 48, she donated a kidney to a stranger after coming across an ad in a weekly Jewish newspaper. The ad stated: "Please help save a Jewish life—New Jersey mother of two in dire need of kidney—Whoever saves one life from Israel it is as if they saved an entire nation."
To make matches, Lipschutz posts in various online groups in the United States and Israel. Donors in Israel may receive "refunds" for loss of earnings, travel expenses, psychological treatment, recovery leave, and insurance. They also qualify for visits to national parks and nature reserves without entrance fees, Lipschutz says.
"There has been an attempt to figure out what would constitute fair compensation without the appearance that people are selling their organs or their loved ones' organs."
Kidneys can be procured from healthy living donors or patients who have undergone circulatory or brain death.
"The real dilemma arises with payment for living donation, which would favor poorer individuals to donate who would not necessarily do so," says Dr. Cheryl L. Kunis, a New York-based nephrologist whose practice consists primarily of kidney transplant recipients. "In addition, such payment for living donation has not demonstrated to improve a donor's socioeconomic status globally."
Living kidney donation has the highest success rate. But organs from young and previously healthy individuals who die in accidents or from overdoses, especially in the opioid epidemic, often work just as well as kidneys from cadaveric donors who succumb to trauma, Kunis says.
In these tragic circumstances, she notes that the decision to donate is often left to an individual's grieving family members when a living will isn't available. A payment toward funeral expenses, for instance, could tip their decision in favor of organ donation.
A similar scenario presents when a patient with a beating heart is on the verge of dying, and the family is unsure about consenting to organ donation, says Jonathan D. Moreno, a professor in the department of medical ethics and health policy at the University of Pennsylvania.
"There has been an attempt to figure out what would constitute fair compensation," he says, "without the appearance that people are selling their organs or their loved ones' organs."
The overarching concern remains the same: Compensating organ donors could lead to exploitation of socioeconomically disadvantaged groups. "What's likely to finally resolve" this bioethics debate, Moreno foresees, "is patient-compatible organs grown in pigs as the basic science of xenotransplants (between species) seems to be progressing."
Cooper, the transplant surgeon at Georgetown, believes more potential donors would come forward if financial barriers weren't an issue. Of the ones who end up giving a part of themselves, with or without reimbursement, "the overwhelming majority look back upon it as an extremely positive experience," he says. After all, "they're lifesavers. They should be celebrated."