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On "Arrested Development," psychotherapist-turned-actor Tobias Funke, played by David Cross, is pathologically afraid of being naked, even in front of his wife.

Of the many wonderfully nonsensical things the TV show “Arrested Development” has introduced us to – the mayonegg, hot ham water, each family member’s interpretation of the chicken dance – one of the most notable is the "never-nude".

On the show, which returns May 26 for a much-anticipated fourth season on Netflix, psychotherapist-turned-actor Tobias Funke suffers from the psychological condition and is pathologically afraid of being naked. He wears denim cut-offs at all times, even in the shower.  

But it's not just a made-up quirk played for laughs. There really are people with a crippling fear of nudity, a condition called gymnophobia.

“There are people who are not comfortable being naked in front of other people — and there are other people who are not comfortable looking at themselves naked,” said Martin Antony, professor of psychology at Ryerson University in Toronto, and author of “The Anti-Anxiety Workbook.”

People can develop phobias – an extreme, irrational fear that negatively impacts a person’s ability to lead a normal life – of just about anything. There are the common phobias like arachnophobia or claustrophobia, but there’s also coulrophobia (fear of clowns), nomophobia (fear of being out of cellphone service) and sesquipedalophobia (fear of long words).

Phobias often develop after a negative experience. A gymnophobic may have been bullied while changing in the middle school locker room, for example. Most people who are afraid of nudity suffer from other anxiety disorders and body image problems.

Some people who are afraid of being naked suffer from eating disorders or body dysmorphic disorder, a mental condition where people believe they are ugly or fat or imperfect when there is little truth to it. People with this disorder often obsess over their appearance, hiding their bodies from themselves or others. Others could simply feel they do not measure up to media images of beautiful bodies and feel nervous about showing off their bodies.

“[It’s] more a general anxiety of their own body image as a comparative basis. We are an increasingly obese nation so the comparison could be stressful, anxiety producing, negative for one’s self-concept and could affect one’s own willingness to expose one’s self in privacy in a relationship,” said Frank Farley, a professor psychology at Temple University.

Also, people with extreme forms of anxiety and obsessive-compulsive disorder (OCD) can sometimes feel uncomfortable about being naked in front of other people, due to the intrusive, compulsive thoughts that accompany the condition.

Experts say they would treat a nudity phobia like other phobias, such as claustrophobia or agoraphobia. They encourage exposure to the feared item in a safe, controlled way. If someone were afraid of being naked in front of a partner, Antony would recommend that the patient try wearing only underwear (cut-offs -- Funke's cover-up of choice --  are also acceptable) and work his or her way to full nudity. Antony also says that therapists would work on cognitive modification, changing the way someone thinks about their own nudity. 

“Most people are not ‘never-nudes,’ but they are ‘not-usually-nudes.’ A lot of people would feel somewhat self-conscious about being naked,” Antony said.

Related stories:

• 3 things we know about the new season of 'Arrested Development'
• Seth Rogen, Kristen Wiig join 'Arrested Development'
• Fear of clowns is no laughing matter

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The woman had lost 11 pounds in the past several months, and told doctors she had cramplike spasms shortly after eating.

Her doctors performed an endoscopy and found that, when she swallowed, her esophagus had the same helical shape as a playground twisty slide.  

X-ray images revealed the startling, corkscrew shape taking form.

"The magnitude of this finding was extraordinary," said Dr. Luc Biedermann, of the University Hospital Zurich, who treated the woman and reported the case in this week's New England Journal of Medicine.

Although the condition is unusual, it has been encountered before. In fact, another elderly female patient, 89 years old, who complained of difficulty swallowing, abdominal pain and frequent belching, also turned out to have her esophagus twisting into a helical shape when she swallowed, according to a 2003 case report in the same journal.

Dr. Michael Vaezi, who specializes in treating "esophageal motility disorders" at Vanderbilt University Medical Center in Tennessee, said he has seen the condition many times.

While primary care doctors may rarely see this disorder, at his center, they "encounter these patients on weekly basis."

Dr. John Pandolfino, a gastroenterologist at Northwestern Memorial Hospital in Chicago, explained that this strange phenomenon occurs because of the way the muscles of the esophagus contract. Normally when a person swallows, the muscle fibers that encircle the top of the esophagus contract first, and then as they relax, the muscles just below them contract, and this wave of contraction continues all the way down to the stomach.

But in a person with this condition, all the muscles contract simultaneously. As a result, rather than moving food downward toward the stomach, the muscles pull the esophagus itself into a spiral shape.

Why this happens, however, is still unknown. Vaezi said "some have speculated that gastroesophageal reflux (GERD) could be playing a role."

While there is no cure for the condition, the doctors in the study tried to treat the patient's symptoms by giving her high-dose proton-pump inhibitor drugs, which are typically used to treat gastroesophageal reflux disease, and long-acting calcium channel-blockers, which Vaezi said can help to scale down the "squeeze" of the esophagus's contractions.  

In this patient's case, neither drug had much of an effect.

In some cases, "Botox of the esophagus has also been tried with limited success," Pandolfino said, "but it only lasts six to 12 months, so it's not a good long-term solution." A last-resort solution may include surgery of the esophageal muscles.

More from MyHealthNewsDaily:

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By Marc Lallanilla, LiveScience

Gray hair — one of the classic signs of aging that can lead to a midlife crisis — may some day be a thing of the past, much to the chagrin of hair-dye manufacturers and Corvette salesmen.

A team of European researchers claims to have found not only the root cause of gray hair, but also a treatment for the condition. Additionally, their treatment may help people with vitiligo, a condition that causes the loss of pigment in patches of skin, they say.

It's been known for years that hair turns gray due to a natural buildup of hydrogen peroxide in hair follicles, which causes oxidative stress and graying. (Hydrogen peroxide solutions have been used for years as a cheap and easy way to "go blonde.") 

In younger people, an enzyme called catalase breaks down hydrogen peroxide into water and oxygen. But lower levels of this enzyme, combined with lower levels of enzymes called MSR A and B that repair hydrogen peroxide damage, cause hair to turn gray as we age.

The researchers, whose findings are published in the experimental-biology publication FASEB Journal, analyzed 2,411 people with vitiligo.

By looking at people with two different kinds of vitiligo — strictly segmental vitiligo (SSV) and non-segmental vitiligo (NSV) — they discovered that both kinds resulted from oxidative stress.

And by applying a topical treatment, a substance called PC-KUS, the researchers successfully treated the discolored skin and eyelashes of people with vitiligo.

Though gray hair isn't always a welcome sign of aging, there's some evidence that suggests it can be an indicator of good health.

Researchers in 2012 found that wild boars with significant graying hair "were actually those in prime condition and with the lowest levels of oxidative damage," researcher Ismael Galván of the Museo Nacional de Ciencias Naturales in Spain said in a statement.

"Far from being a sign of age-related decline, hair graying seems to indicate good condition in wild boars," Galván said.

Nonetheless, many people will go to extreme lengths to hide any hint of aging, including gray hair.

"For generations, numerous remedies have been concocted to hide gray hair," Dr. Gerald Weissmann, editor-in-chief of FASEB Journal, said in a statement. "But now, for the first time, an actual treatment that gets to the root of the problem has been developed."

The treatment will be welcome news to people with severe or unsightly cases of vitiligo. "This condition, while technically cosmetic, can have serious socio-emotional effects," Weissmann said. "Developing an effective treatment … has the potential to radically improve many people's lives."

More from LiveScience: 

• 5 Reasons Aging Is Awesome
• Zoo Animals Face Old Age and Illness: Gallery
• The Top 10 Worst Hereditary Conditions

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By Meghan Holohan, NBC News contributor

If you’re a dog person, you may have more in common with your fellow dog owners than you even realize. 

New research shows that two strangers who both own dogs are more likely to share similar skin bacteria than a married couple without a dog in the home. The study also found that dogs have more skin bugs in common with their human owner than other dogs.

Researchers examined the skin of people who lived together – couples, couples with dogs, couples with children and couples with children and dogs – and found that the family dog very generously shares his skin bugs with his owners. The groups with dogs in the home shared more skin bacteria than any of the other cohabitating groups studied. Not surprisingly, doggy affection is behind all this sharing – dogs transmit their skin microbes to their people via tongue-to-skin, skin-to-skin or paw-to-skin contact.

If you’re not a dog person, you might find all of this a little gross. But remember, our skin is already teeming with thousands of kinds of bacteria, and those microbial colonies help keep us healthy by bolstering our immune systems or aiding digestion, for example. Plus, the researchers assure that picking up some doggy bacteria is not harmful to humans.

“Most of the dogs’ [microbes] will be more beneficial than harmful,” says Rob Knight, a co-author of the new report and an associate professor at the University of Colorado, Boulder. He points out that past studies have shown that kids who grow up with a dog in the home have lower rates of asthma and allergies.

Knight and his colleagues wanted to find out how cohabitating couples spread microbes, and if they contributed to each other’s microbiome – that’s the entire collection of microorganisms living in an environment (in this case, our bodies). They took oral, skin, and fecal samples from 159 people: 17 families with cohabitating children from six months to 18 years old; 17 families with one or more dogs but no children; eight families with both children and canines; and 18 families with no dogs or kids. The researchers also took samples oral, skin, and fecal samples from the dogs. They then analyzed all the samples to see how much overlap existed.  

He suspected that couples with young children would have the most microbes in common; kids seem like a hotbed of microbes and caring for them means couples face the same exposure. But that’s not the case – families with canine family members shared more microbes. Interestingly, the same isn't true for cat owners, possibly because our feline friends are less social. (Besides, everyone knows cats hate sharing.) When Spot bestows a lick of love, he’s also giving a gift of betaproteobacteria, and when he offers a paw shake it comes with a side of actinobacteria. These two doggy microbes were most often found on their owners’ skin.    

Even though the dog-human microbial bond is strong, Knight notes that families show evidence of having similar microbiomes. Even still, each person’s microbial makeup is singular. 

“It is fascinating how different and unique that the microbial communities on people are,” he says.

While it might make our skin crawl to consider that we have something like 100 trillion microbes in and on our bodies compared to our 10 trillion cells, Knight assures us that microbes are friendly.

“Microbes are actually helpful,” he says. “If most of the microbes were out to get us, we’d really be in trouble.”

The study appears at the online journal eLife. And if you're interested in participating in research mapping human microbes, sign up here.

Related: 

• Roller derby skaters trade bumps, bruises and bacteria

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Don Draper is an incredibly sexy (if fictional) man, with his square jaw line and strong chin. And that isn’t just personal opinion. Research has shown that chiseled jaws and strong chins appear more masculine and are considered universally attractive. But a new study challenges the idea of universally attractive features -- and finds that there is no one chin that is sexier than others.

“Chins are kind of a funny thing. It seems like a random thing to look at, but chins are like a hallmark of modern human anatomy,” says Seth Dobson, an assistant professor in the anthropology department at Dartmouth College. “No other animals have chins.”

For years, Dobson has speculated about why only humans have chins and what purpose they serve. While he hasn’t come to any concrete conclusions, he wondered if chins impact how we select mates. Some experts believe that we pick partners based on universal facial attractiveness—a set of traits, such as symmetrical facial features, that are overwhelmingly deemed hot (and biologically superior). Dobson thought that if women mated with men who had strong chins and men bred with women with smaller, weaker chins that skeletons would show this.

“We reasoned that if they are universal [then] the preferences actually influence [skeletal] evolution and that people would have the same chin shapes,” he says. “That is not the case.”

Dobson looked at 180 male and female skeletons that originated from nine different Old-World geographic locations including, Australia, Eastern and Southern Africa, Southeastern, Central, and Eastern Asia, and Northern, Eastern, and Western Europe. After creating contour tracings of the chins, a computer analyzed their shapes. Dobson found there isn’t one dominant preferred chin shape for men or women in any region.    

“The preferences aren’t actually universal,” he says, but adds a caveat: “I don’t think that our result undermine that there is strong preference [for certain chins].”

These results might mean that people don’t pick partners based only on universally attractive traits, he explains. Sure, a strong chin might seem sexier, but the man who owns the chin might not have a great personality. And we can’t all marry men with Don Draper chins.

“[A woman] may express a preference for a chin, but if you look at who she is actually choosing as a partner his chin may look different. In the real world, people choose their partners for a wide variety of reasons that may not be entirely clear,” says Dobson. “There is physical attractiveness as a sense that you have that you cannot really explain.”

Also, the skeletons are all between 100 and 200 years old, meaning they lived long before Western ideals of beauty became pervasive.     

“One thing is possible, this is speculation, it is possible that the preferences that look to be universal cross culturally today maybe weren’t important in the past,” Dobson says. “But they may be important in the future.”

The paper was published online earlier this month in the journal PLoS One. 

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Need to remember some important facts for that big presentation at work? Clench your right hand while preparing to remember. When giving that talk, ball up your left hand and you’ll call to mind those details, no problem.  

That’s the finding from a new study authored by Ruth Propper, an associate professor and director of the cerebral lateralization laboratory at Montclair State University. Propper has long been intrigued by how body movements impact how the brain works. While most people realize that the brain influences the body (the brain tells your arm there is an itch, and you feel it), less is understood about how the body sways the brain.

Past research suggests that clenching our hands can evoke emotions. When people ball up their right hands, for example, the left sides of their brains become more active, causing what’s known as “approach emotions,” feelings such as happiness or excitement. By squeezing the left hand, people engage the right side of the brain, which controls “withdrawal emotions” such as introversion, fear, or anxiety. (It probably seems like these might be less useful, but they come in handy in dangerous situations.)

Propper theorized that if clenching hands impacted feelings, these gestures might influence the brain in other ways.

To learn how hand clenching influenced memory and recall, she asked 51 right- handed subjects to memorize 72 words and randomly assigned each person to one of five hand-clenching groups or a control group that did nothing. Only righties were included because lefties exhibit better episodic memory overall so they’d have an unfair advantage. She found the perfect combination for better memory and recall occurs when a subject clenches his right hand while memorizing and balls up his left hand while trying to recall the memory. 

“It is interesting to compare to not clenching at all. It’s almost 15 percent better [to clench right then left] than sitting there,” she says. 

While a 15 percent improvement is on the edge of being statistically significant, Propper notes 15 percent can be the difference between an A and a C on test.

Propper admits that more research needs to be conducted on how bodily movements enhance brain function, but she recommends that people try squeezing their hands to aid with memory.

“I would say that it would be worth trying,” Propper says. Take parking your car in the parking lot.  “(A)s you park you can clench your right hand and when you are trying to find it, clench your left hand.”

The paper appears in PLoS One. 

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Some sound like mortar fire, others like somebody just stepped on a mouse.

“I have world famous kitten sneezes,” says Susan Frykholm, a 31-year-old multimedia sales specialist from Seattle. “I’m not trying to be cute but people usually start laughing at how ‘precious’ they are.”

“Mine are like a revolutionary war cannon,” says Dan Fine, a 54-year-old IT consultant who is also from Seattle.

We each have our own individual sneezing style. But what, exactly, determines whether those sneezes come out dainty and demure or whether they blow down the whole dang house?

“Sneezes are like laughter,” says Dr. Alan Hirsch, a neurologist, psychiatrist and founder of the Smell & Taste Treatment and Research Foundation in Chicago. “Some [laughs] are loud, some are soft. And it’s similar with sneezing. It will often be the same from youth onward in terms of what it sounds like.”

Hirsch says he doesn’t know of any studies that have been conducted on various sneezing styles and what they might mean, but says he does believe the way we sneeze reflects some component of the personality.

“It’s more of a psychological thing and represents the underlying personality or character structure,” he says.

A person who’s demonstrative and outgoing, for instance, would most likely have a loud explosive sneeze, whereas someone who’s shy might try to withhold their sneezes, resulting in more of a Minnie Mouse-type expulsion.

Tara Spicer, a 29-year-old copywriter from Mountlake Terrace, Wash., has her own theory about why she sneezes the way she does.

“I'm a sneeze stifler,” she says. “I've always pinched my nose to mute the noise. I think it's a subconscious rebellion against my grandmother, who raised me much of my life, and took pride in her ear-shattering siren-sneeze.”

Others describe their sneezes as screams or trills or “triple threats,” sneezes that come in threes. Just as with other basic body functions (we’re thinking of coughs or hiccups or burps here), everybody’s got their own signature style.

Why do we sneeze in the first place?

“In general, sneezing is an involuntary phenomenon, part of the body’s mechanism of defense, a way of clearing out bacteria or other agents that would be injurious,” says Dr. Gordon Siegel, a Chicago-area otolaryngologist (ear, nose and throat doctor). “That being said, you can control to a degree the way it comes out.”

Siegel, an assistant clinical professor at Northwestern Feinberg School of Medicine, points to an acquaintance whose sneezes always incorporate a particularly colorful expression.

“When he sneezes, he likes it to come out saying ‘horsesh*t’ and he’s got it down,” he says. “There is partial control of the final product.”

The shape of our nose or the bone structure of our face might contribute a small degree to certain sneezing styles much in the same way the resonance of our voice is affected by our anatomy, says Siegel. But “what we perceive as the sneezing sound is not really affected significantly by the nose structure.”

For the most part, people don’t really think that much about sneezes, he says. They just happen.

Hirsch, however, has given the practice some thought and adds this final insight.

“When we think about sneezing, it’s almost orgasmic in its quality,” he says. “By giving in to it, you’re experiencing the positive pleasures of a nasal orgasm. So if someone is more sexually repressed, they may withhold it. But if they’re hedonistically-oriented and like pleasure, they may sneeze loudly and strongly.”

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You might credit the legendary Scottish male virility of past time to single malt whiskey, or the sometimes brutal weather, or the fact that haggis is the national dish, but a Dutch researcher is proposing another answer:

Chuck Burton / AP

"Men wearing a kilt experience a strong sense of freedom and masculinity," says a researcher. Here Tim Propst, of Lincoln County, N.C., throws a hammer during the Grandfather Mountain Highland Games in Linville, N.C. in July 2012.

It was the kilts.

Kilts, worn as they were meant to be worn, without underwear, lets our laddies swing freely in the breeze, creating, according to researcher Erwin Kompanje, the “ideal physiological scrotal environment.” Exposed to the bracing Highland coolness, testicles will make robust sperm.

The modern man’s “scrotal environment” is pretty confined these days, what with underwear and pants that hold our testicles close to the body and its 98.6-degree heat, Kompanje, a senior researcher in the department of intensive care at Erasmus University in Rotterdam, told NBCNews.com. But as he pointed out in a paper published online in the Scottish Medical Journal, “adequate spermatogenesis requires a temperature about 3 degrees [Celsius] lower than normal body temperature.” (That would translate to about 93 degrees Fahrenheit, compared to the normal body temperature of 98.6 Farenheit.)

Testicular temperature is regulated by the cremaster muscle – the muscle that covers the testicles -- that raises and lowers the scrotum in response to heat and cold. “The cremaster reflex only works, and has any sense, when the scrotum is hanging free,” Kompanje said. “In tight trousers it cannot work. In a naked man, or a man wearing a kilt, it can and will.”

Kompanje stresses that he’s only proposing a hypothesis based partly on his own fascination with things Scottish – he sometimes wears a kilt for special ceremonial occasions – and anecdotal evidence that kilt-wearing is good for sperm, and scientific evidence that sperm production wilts under high scrotal temperatures.

“I searched the scientific literature, and I found nothing on the subject,” he said. “Then I searched on sperm quality and found many scientific papers related to high scrotal temperature and tight clothing. So as 1+1=2, I formed the hypothesis that wearing a skirt-like garment (as a kilt) without underwear would help to improve sperm quality.”

There’s been a lot of debate in science about whether modern western men have poorer sperm quality and fewer sperm overall than they did 50 or 100 years ago. Environmental toxins, stress, smoking, diet, have all been implicated in the decline.

Temperature is often blamed, too, which is why doctors advise men not to put laptop computers on their laps. When doctors in Germany experimented with a “nocturnal scrotal cooling” device – crotch air conditioning – in men with fertility problems, they found “a significant increase in sperm concentration and total sperm count…after 8 weeks” according to a 2005 journal article.

So Kompanje may well be correct when he proposes kilt wearing as a possible solution to dropping sperm quality.

This raises the question, however, of whether a man wearing a kilt will get any opportunities to send his swimmers into the pool.  

Kompanje isn’t worried. “I found literature, and I have experienced this myself, that women like to see a man wearing a kilt. It can be very masculine and sexy.”    

“Wearing a kilt has strong psychological benefits,” he writes in his journal article. “A kilt will get you noticed no matter where you are. Research indicates that men wearing a kilt experience a strong sense of freedom and masculinity…The kilt gives a man a sensuous awareness of his own body and how it will be seen by others.”

Kompanje acknowledges there’s no proof testicles will be happier under kilts, so he proposes a controlled trial with regular scrotum temperature taking and sperm quality monitoring of some men wearing pants and others wearing kilts. One incentive to volunteer might be what Kompanje argues is the “positive attention from sexual admirers” associated with kilts.

Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young Ph.D., of "The Chemistry Between Us: Love, Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com), now on sale.

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You're on a stage, lights hot and glaring, watching the large audience you’ll soon be addressing file in. How is your body reacting?

You’re most likely jittery, your heart pounding through your rib cage and your breath quickening. Your legs may very well be able to run a marathon at this moment. And—oh great—your mouth just became super dry.

These reactions are not exactly conducive to standing in place and addressing a crowd, right? You’re not alone. Fear of public speaking, or glossophobia, is estimated to affect 75 percent of adults.

But such reactions, as it turns out, are the body’s natural way of helping us cope with stressful situations. According to a new study published in Clinical Psychological Science, rethinking the way we perceive stress may actually improve our physical and mental performance.

In the study, 73 adults, half of whom met the diagnostic criteria for social anxiety disorder, underwent the Trier Social Stress Test. Designed to induce stress in a socially-evaluative situation, the test gives participants three minutes to prepare a five-minute speech about their strengths and weaknesses to two judges. Immediately following the speech, subjects must count backwards by sevens beginning with the number 996.

Before beginning the test, half of the participants were randomly assigned to read information regarding the evolutionary advantages of the body’s stress response. Specifically, they were informed that “the increase in arousal [they] may feel during stress is not harmful,” and that they should “reinterpret [their] bodily signals during the upcoming public speaking task as beneficial.” They also read summaries of three psychological studies that evaluated the benefits of stress.

The other half of the participants did not undergo this “anxiety preparation” task.

Purposely, the judges provided negative, non-verbal feedback throughout the speeches by head-shaking, stone-faced expressions, and tapping annoyingly on their clipboards. If the participant made a mistake, the judge instructed them to start over.

Before, during, and after the stress test, cardiovascular measures of heart rate and blood pressure were assessed in all participants.

Participants who did not undergo anxiety preparation showed a much greater cardiovascular stress response. The group that went into the stress test informed about the benefits of stress, on the other hand, reported feeling that they had more resources to cope with public speaking.

Jeremy Jamieson, lead author of the study and assistant professor of psychology at University of Rochester, says that his work “shares the underlying concept that if you can alter cognitive factors, you can alter downstream outcomes.”

“Feelings of arousal, like sweaty palms or a racing heart that are typically construed negatively can instead be viewed as tools to help cope with acute stress,” he says.

Interestingly, despite greater fear of public speaking, individuals with social anxiety disorder did not show more physiological arousal than their non-anxious peers.

The authors conclude that our experiences of short-term stress are shaped by how we interpret our body. “Viewing one’s biological responses as beneficial will increased the ratio of perceived resources versus task demands,” says Jamieson. “Our reappraisal instructions focus on educating individuals that stress is an adaptive response.”

So the next time you feel the jitters of public speaking overtaking you, remind yourself that the human body is designed to help us cope with this stress, despite our trembling legs and dry mouths.

Above all, be grateful—this ability likely evolved when our ancestors had to outrun predators, not give speeches!

Jordan Gaines is a science writer and neuroscience grad student at Penn State College of Medicine. You can check out her blog, Gaines on Brains, and follow her at @GainesOnBrains.

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As a neurologist, Dr. Sam Berkovic sees many patients who frequently faint. These people say they feel weak in the knees after experiencing something unpleasant, perhaps seeing blood or being dehydrated. He began suspecting that fainting, also known as vasovagal syncope, runs in families.

And he appears to be on to something. A study by Berkovic, published today in the journal Neurology, finds that fainting may be genetic, and for some families only one gene causes it.

On average, about a third of the world’s population are frequent fainters. ”(I)t’s usually trivial, not a serious health issue,” says Berkovic, a laureate professor in the department of medicine at Austin Health at the University of Melbourne in Australia.

People who suffer from vasovagal syncope faint after encountering a trigger, which can be something like seeing blood, being dehydrated, feeling stress, or experiencing pain. While losing consciousness feels scary, vasovagal syncope is normally harmless. But Berkovic believes that understanding why people swoon might mean researchers can someday prevent them, saving fainters from accidents—and embarrassment.

To determine genetic underpinnings, Berkovic and his colleagues recruited 44 families with members who shared a history of fainting. Six of these families had a large number of fainters, bolstering the researchers’ belief that fainting was genetic. One family had 14 members who experienced vasovagal syncope and another had 30 individuals from three different generations.   

The researchers gathered DNA samples and also asked the family members to answer questionnaires about their general health, the onset of fainting, and what triggers their swoons. After analyzing the DNA, the researchers found that six of the 44 families showed strong evidence of a genetic link. And, the family of 30 fainters all shared a strong linkage to one chromosome, 15q26. These results show that a vasovagal syncope is genetic.  

While discovering a genetic link for fainting wasn’t a surprise, Berkovic admits he was amazed to learn that the triggers differed among family members. If a mother faints at the sight of blood, for example, her son might swoon when dehydrated. Berkovic says we don’t fully understand how triggers work, but this paper suggests it doesn’t seem to be controlled by genetics.

He hopes that future research will shed light on what controls the triggers, allowing for a better understanding of vasovagal syncope. Some people’s aversion to blood, for example, is so severe they refuse blood tests because they fear fainting. By understanding the triggers, researchers might be able to treat them.

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