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Aging, Genetics, Immunology, Infectious Disease, Research, Stanford News

In human defenses against disease, environment beats heredity, study of twins shows

In human defenses against disease, environment beats heredity, study of twins shows

Pfc. Lane Higson and Pfc. Casey Higson, identical twins serving in Iraq with the Enhanced Combat Aviation Brigade, 1st Infantry Division. The twins, natives of Myrtle Beach, S.C., joined the Army together and have not separated since.I’m one of those people who’ve paid to have their genomes analyzed for the purpose of getting a handle on susceptibility to this or that disease as time goes by. So it was with great interest that I came across a new study of twins conducted by immunologist Mark Davis, PhD, and fellow Stanford investigators. The study, published in CELL, shows that our environment, more than our heredity, plays the starring role in determining the state of our immune system, the body’s primary defense against disease. This is especially true as we age.

Improving gene-sequencing technologies have focused attention on the role of genes in diseases. But the finding that the environment is an even greater factor in shaping our immune response should give pause to anyone who thinks a whole-genome test is going to predict the course of their health status over a lifetime.

“The idea in some circles has been that if you sequence someone’s genome, you can tell what diseases they’re going to have 50 years later,” Davis told me when I interviewed him for a news release I wrote on the study. But, he noted, the immune system has to be tremendously adaptable in order to cope with unpredictable episodes of infection, injury and tumor formation.

Davis, who heads Stanford’s Institute for Immunity, Transplantation and Infection, is worth taking seriously. He’s made a number of major contributions to the field of immunology over the last 30 years or so.  (Not long ago, I wrote an article about one of those exploits for Stanford Medicine.)

To find out whether the tremendous differences observed between different people’s immune systems reflec tunderlying genetic differences or something else, Davis and his colleagues compared members of twin pairs to one another. Identical twins inherit the same genome, while fraternal twin pairs are no more alike genetically than regular siblings, on average sharing 50 percent of their genes. (Little-known fun factoid: The percentage can vary from 0 to 100, in principle, depending on the roll of the chromosomal dice. But it typically hovers pretty close to 50 percent, just as rolling real dice gives you a preponderance of 6s, 7s, and 8s. Think of a Bell curve.)

Because both types of twins share the same in utero environment and, usually, pretty close to the same childhood environment as well, they make great subjects for contrasting hereditary versus environmental influence. (If members of identical-twin pairs are found to be no more alike than members of fraternal-twin pairs with respect to the presence of some trait, that trait is considered to lack any genetic influence.)

In all, the researchers recruited 78 identical-twin pairs and 27 pairs of fraternal twins and drew blood from both members of each twin pair. That blood was hustled over to Stanford’s Human Monitoring Center, which houses the latest immune-sleuthing technology under a single roof. There, the Stanford team applied sophisticated laboratory methods to the blood samples to measure more than 200 distinct immune-system cell types, substances and activities.

Said Davis: “We found that in most cases – including your reaction to a standard influenza vaccine and other types of immune responsiveness – there is little or no genetic influence at work, and most likely the environment and your exposure to innumerable microbes is the major driver.”

It makes sense. A healthy human immune system has to continually adapt to its encounters with hostile pathogens, friendly gut microbes, nutritional components and more.

“The immune system has to think on its feet,” Davis said.

Previously: Knight in lab: In days of yore, postdoc armed with quaint research tools found immunology’s Holy Grail, Deja vu: Adults’ immune systems “remember” microscopic monsters they’ve never seen before and Immunology escapes from the mouse trap
Photo by DVIDSHUB

Imaging, Neuroscience, Research, Science, Stanford News

New insights into how the brain stays bright

New insights into how the brain stays bright

Neon brainAxel Brunger, PhD, professor and chair of Stanford’s Department of Molecular and Cellular Physioogy , and a team composed of several Stanford colleagues and UCSF scientists including Yifan Cheng, PhD, have moved neuroscience a step forward with a close-up inspection of a brain-wide nano-recycling operation.

A healthy adult brain accounts for about 2 percent of a healthy person’s weight, and it consumes about 20 percent of all the energy that person’s body uses. That’s a lot of sugar getting burned up in your head, and here’s why: Incessant chit-chat throughout the brain’s staggeringly complex circuitry. A single nerve cell (of the brain’s estimated 100 billion) may communicate directly with as many as a million others, with the median in the vicinity of 10,000.

To transmit signals to one another, nerve cells release specialized chemicals called neurotransmitters into small gaps called synapses that separate one nerve cell in a circuit from the next. The firing patterns of our synapses underwrite our consciousness, emotions and behavior. The simple act of tasting a doughnut requires millions of simultaneous and precise synaptic firing events throughout the brain and, in turn, precisely coordinated timing of neurotransmitter release.

You’d better believe these chemicals don’t just ooze out of nerve cells at random. Prior to their release, they’re sequestered within membrane-bound packets, or vesicles, inside the cells. Every time a nerve cell transmits a signal to the next one – which can be more than 100 times a second – hundreds of tiny chemical-packed vesicles approach the edge of the first nerve cell and fuse with its outer membrane, like a small bubble merging with a larger one surrounding it. At just the right time, numerous vesicles’ stored contents spill out into the synapse, to be quickly taken up by receptors dotting the nearby edge of the nerve cell on the synapse’s far side, where, like little electronic ones and zeroes in a computer circuit, they may either trigger or impede the firing of an impulse along that next nerve cell.

Each instance of bubble-like fusion – and this happens not only in neurotransmitter release but in hormone secretion and other processes throughout the body – is carefully managed by a complex of interconnecting proteins, collectively known as the SNARE complex. The molecular equivalent of a clamp, the SNARE complex guides the vesicle ever nearer to the nerve-cell’s surface and then, at just the right moment, squishes it up against the cell’s outer membrane. The vesicle bursts, spilling its contents into the synapse.

Myriad repetitions of this process typify the average day in the life of the average nerve cell. This requires not only a ton of energy (which I guess is where the doughnut comes in) but ultra-efficient recycling. The entire SNARE complex must be constantly disassembled, then reassembled. In a new study in Nature, Brunger and his associates snagged a set of near-atomic-scale snapshots of the SNARE complex as well as the molecular machinery that recycles its components, allowing them to make sophisticated guesses about how the whole thing works. (See the Howard Hughes Medical Institute’s news release on the study here.)

This has been a long time coming. In fact, Brunger’s lab first determined the molecular structure of the SNARE complex, via X-ray crystallography, in 1998. The careful decades-long process of tracking down the SNARE complex’s components and their interactions won Stanford neuroscientist Tom Sudhof, MD, the 2013 Nobel Prize in Medicine. But despite its immense importance, you probably haven’t heard much about it. Studies of molecular structures are in general opaque to lay readers, complicated systems such as the SNARE complex all the more so. The popular press pays attention to the awarding of the Nobel, but seldom to the long, towering staircase of incremental discoveries that was climbed to earn it.

Previously: Revealed: The likely role of Parkinson’s protein in the healthy brain, Step by step, Sudhof stalked the devil in the details, snagged a Nobel and But is it news? How the Nobel prize transformed “noteworthy” into “newsworthy”
Photo by Carolyn Speranza

Genetics, Research, Science, Stanford News

Show-off! Protein upstages DNA by ordering amino-acid add-ons

Show-off! Protein upstages DNA by ordering amino-acid add-ons

Show-offEvery living cell is a metropolis in which the vast bulk of work is performed by phenomenally productive laborers called proteins. Proteins work so hard – and the work that must be done in a cell changes so rapidly – that turnover in the labor force is immense. To maintain the brisk pace of life inside a cell, new proteins must constantly be assembled.

The machines responsible for that assembly are called ribosomes – as many as 10 million of them within a single mammalian cell, each capable of stapling together up to 200 amino acids (the building blocks of proteins) per second. The resulting amino-acid strings immediately fold themselves into characteristic structures reflecting their precise composition.

There are about 20 different varieties of amino acids, so the number of possible combinations a ribosome can make, in theory, is mind-boggling. But a ribosome doesn’t just piece together whatever protein suits its passing fancy. It carefully heeds instructions stored on lengthy strands of DNA inside the cell’s nucleus, in a massive library known as the genome: a gigantic set of genes (the recipes for proteins), written in a ribosome-readable chemical code. But genes never leave the nucleus, and ribosomes never enter it.

Bridging that physical gap is a substance called messenger RNA, chemically similar to DNA but physically far more flexible and athletic. Like couriers carrying copies of a royal edict, messenger RNA molecules constantly exit the nucleus, where they were produced as portable copies of one gene or another. They head for the watery suburbs of the cell where protein construction takes place. And there, they find a ribosome, climb in, are fed through the ribosome’s molecular machinery, and get spit out like spent ticker tape once the ribosome has finished reading the recipe and assembling the specified protein product.

Under ordinary circumstances, ribosomes faithfully follow genetic instructions. But with all that whirling and whirring, sometimes things go wrong: The mRNA molecule or the ribosome is defective or, for some other reason, the protein-in-the-making is faulty.

Misspelled or misfolded proteins can wreak havoc. Happily, cells have “quality control” teams that can pick apart poorly produced proteins, tear up malfunctioning messenger RNA and retire rotten ribosomes.

In exploring that process, Stanford biochemist Onn Brandman, PhD, and colleagues at the University of California and University of Utah may have turned molecular-biological dogma on its head. In a new study in Science, Brandman and his associates report that they’ve identified a member of the quality-control squad, a protein called rqc2, that gloms onto stalled ribosomes – and then does something no protein has ever previously been shown to do: call out for the delivery of two particular amino acids, which get attached in random sequences to the aberrant protein under construction.

“Our results defy textbook science, showing for the first time that the building blocks of a protein, amino acids, can be assembled without the standard blueprints,” Brandman told me. “In the case we observed, neither DNA nor messenger RNA but a protein directs that a pair of amino acids be randomly added, in small stretches, to the ends of proteins that have stalled mid-synthesis. The function of these ‘tails’  isn’t known. But in yeast, elevated levels are correlated with proteotoxic stress, a condition that in humans may be involved in disorders such as Alzheimer’s, Parkinson’s and Huntington’s disease.”

Previously: Key to naked mole rat longevity may be related to their body’s ability to make proteins accurately and Night of the living dead gene: Pseudogene wakes up, puts chill on inflammation
Photo by Iain Farrell

Big data, Cancer, Cardiovascular Medicine, Fertility, Men's Health, Research, Stanford News

Male infertility can be warning of hypertension, Stanford study finds

Male infertility can be warning of hypertension, Stanford study finds

sperm graffitiA study of more than 9,000 men with fertility problems links poor semen quality to a higher chance of having hypertension and other health conditions. The findings suggest that more-comprehensive examinations of men undergoing treatment for infertility would be a smart idea.

About a quarter of the adults in the United States (and in the entire world) have hypertension, or high blood pressure. Although it’s the most important preventable risk factor for premature death worldwide, hypertension often goes undiagnosed.

In a study published today in Fertility and Sterility, Stanford urologist Mike Eisenberg, MD, PhD, and his colleagues analyzed the medical records of 9,387 men, mostly between 30 and 50 years old, who had provided semen samples in the course of being evaluated at Stanford to determine the cause of their infertility. The researchers found a substantial link between poor semen quality and specific diseases of the circulatory system, notably hypertension, vascular disease and heart disease.

“To the best of my knowledge, there’s never been a study showing this association before,” Eisenberg told me when I interviewed him for a press release about the findings. “There are a lot of men who have hypertension, so understanding that correlation is of huge interest to us.”

In the past few years, Eisenberg has used similar big data techniques to discover links between male infertility and cancer and heightened overall mortality, as well as between childlessness and death rates in married heterosexual men.

Eisenberg sums it all up and proposes a way forward in the release:

Infertility is a warning: Problems with reproduction may mean problems with overall health … That visit to a fertility clinic represents a big opportunity to improve their treatment for other conditions, which we now suspect could actually help resolve the infertility they came in for in the first place.

Previously: Poor semen quality linked to heightened mortality rate in men, Men with kids are at lower risk of dying from cardiovascular disease than their childless counterparts and Low sperm count can mean increased cancer risk
Photo by Grace Hebert

Immunology, Neuroscience, Research, Stanford News

Blocking a receptor on brain’s immune cells counters Alzheimer’s in mice

Blocking a receptor on brain’s immune cells counters Alzheimer’s in mice

brain in motionAttention, nerve cells: It’s not all about you.

As a new study in the Journal of Clinical Investigation led by Stanford neuroscientist Kati Andreasson, MD, shows, blocking the action of a single molecule situated on the surfaces of entirely different brain cells reversed memory loss and a bunch of other Alzheimer’s-like features in experimental mice.

The very term “neuroscience” strongly suggests that nerve cells, a.k.a. neurons, are the Big Enchilada in brain research – and, let’s face it, you wouldn’t want to leave home without them. But they’re far from the entire picture. In fact, neurons account for a mere 10 percent of all the cells in the brain. It may be that the mass die-off of nerve cells in the brains of people with Alzheimer’s disease may largely occur because, during the course of aging, another set of key players ensconced in that mysterious organ inside our skull and  known collectively as microglia begin to fall down on the job.

In  a release I wrote to explain the study’s findings in lay terms, I described microglia as the brain’s very own, dedicated immune cells:

A microglial cell serves as a front-line sentry, monitoring its surroundings for suspicious activities and materials by probing its local environment. If it spots trouble, it releases substances that recruit other microglia to the scene … Microglia are tough cops, protecting the brain against invading bacteria and viruses by gobbling them up. They are adept at calming things down, too, clamping down on inflammation if it gets out of hand. They also work as garbage collectors, chewing up dead cells and molecular debris strewn among living cells – including clusters of a protein called A-beta, notorious for aggregating into gummy deposits called Alzheimer’s plaques, the disease’s hallmark anatomical feature. … A-beta, produced throughout the body, is as natural as it is ubiquitous. But when it clumps into soluble clusters consisting of a few molecules, it’s highly toxic to nerve cells. These clusters are believed to play a substantial role in causing Alzheimer’s.

“The microglia are supposed to be, from the get-go, constantly clearing A-beta, as well as keeping a lid on inflammation,” Andreasson told me. If their job performance heads downhill – as seems to occur during the aging process – things get out of control. A-beta builds up in the brain, inducing toxic inflammation.

But by blocking the activity of a single molecule – a receptor protein on microglial cells’ surfaces  – Andreasson’s team got those microglia back on the job. They resumed chewing up A-beta, quashing runaway neuro-inflammation, squirting out neuron-nurturing chemicals. Bottom line: the Alzheimer’s-prone experimental animals’ IQs (as measured by mousey memory tests) rose dramatically.

Aspirin and similar drugs also tend to shut down the activity of this microglial receptor, which may or may not explain why their use seems to stave off the onset of Alzheimer’s in people who start using them regularly (typically for unrelated reasons) before this memory-stealing syndrome’s symptoms show up. But aspirin et al. do lots of other things, too – some good, some bad. The new findings suggest a compound carefully tailored to block this receptor and do nothing else might be a weapon in the anti-Alzheimer’s arsenal.

Previously: Another big step toward building a better aspirin tablet, Untangling the inflammation/Alzheimer’s connection and Study could lead to new class of stroke drugs
Photo by Henry Markham

Aging, In the News, Neuroscience, Research, Science, Stanford News

Stanford research showing young blood recharges the brains of old mice among finalists for Science Magazine’s Breakthrough of the Year

Stanford research showing young blood recharges the brains of old mice among finalists for Science Magazine's Breakthrough of the Year

ballot box

Stanford research showing that an infusion of young blood recharges the brains of old mice is one of the finalists for Science magazine’s annual contest for People’s Choice for Breakthrough of the Year. Today is the last day to cast your vote. Click here if you’d like to support the work, which could lead to new therapeutic approaches for treating dementia.

Several months ago, I had the pleasure of helping break the news about this great piece of research. So, let’s face it, I take a certain amount of pride in the amount of news coverage it received and the attention it’s getting now.

But the real credit goes to Stanford neuroscientist Tony Wyss-Coray, PhD, along with his able lead author Saul Villeda, PhD, and colleagues. This important discovery by Wyss-Coray’s team revealed that infusing young mice’s blood plasma into the bloodstream of old mice makes those old mice jump up and do the Macarena – and perform a whole lot better on mousey IQ tests.

Infusing blood plasma is hardly a new technique. As Wyss-Coray told me when I interviewed him for my release:

“This could have been done 20 years ago….You don’t need to know anything about how the brain works. You just give an old mouse young blood and see if the animal is smarter than before. It’s just that nobody did it.”

And after all, isn’t that what breakthroughs are all about? It’s still too early to say, but this simple treatment – or (more likely) drugs based on a better understanding of what factors in blood are responsible for reversing neurological decline –  could someday turn out to have applications for Alzheimer’s disease and much more.

At last count, the Wyss-Coray’s research is neck-and-neck with a competing project for first place. If you think, as I do, that a discovery with this much potential deserves a vote of confidence make sure to take a moment this afternoon to cast your virtual ballot.

Previously: The rechargeable brain: Blood plasma from young mice improves old mice’s memory and learning, Old blood makes young brains act older, and vice versa and Can we reset the aging clock, once cell at a time?
Photo by FutUndBeidl

Genetics, History, Immunology, Research, Science, Stanford News

Knight in lab: In days of yore, postdoc armed with quaint research tools found immunology's Holy Grail

Knight in lab: In days of yore, postdoc armed with quaint research tools found immunology's Holy Grail

charging knightA human has only about 25,000 genes. So, it’s tough to imagine just how our immune systems can manage to recognize potentially billions of differently shaped microbial or tumor-cell body parts. But that’s precisely what our immune systems have to do, and with exquisite precision, in order to stomp invading pathogens and wanna-be cancer cells and leave the rest of our bodies the heck alone.

How do they do it?

Stanford immunologist Mark Davis, PhD, tore the cover off of immunology in the early 1980s by solving that riddle. As I wrote in  “The Swashbuckler,” an article in the latest issue of Stanford Medicine, T cells are one of two closely related, closely coordinated workhorse-warrior cell types that deserve much of the credit for the vertebrate immune system’s knack of carefully picking bad guys of various stripes out of the lineup and attacking them:

[Q]uite similar in many respects, B cells and T cells are more like fraternal than identical twins. B cells are specialized to find strange cells and strange substances circulating in the blood and lymph. T cells are geared toward inspecting our own cells for signs of harboring a virus or becoming cancerous. So it’s not surprising that the two cell types differ fundamentally in the ways they recognize their respective targets. B cells’ antibodies recognize the three-dimensional surfaces of molecules. T cells recognize one-dimensional sequences of protein snippets, called peptides, on cell surfaces. All proteins in use in a cell eventually get broken down into peptides, which are transported to the cell surface and displayed in molecular jewel cases that evolution has optimized for efficient inspection by patrolling T cells. Somehow, our inventory of B cells generates antibodies capable of recognizing and binding to a seemingly infinite number of differently shaped biological objects. Likewise, our bodies’ T-cell populations can recognize and respond to a vast range of different peptide sequences.

In the late 1970s, scientists (including then-graduate student Davis, who is now director of Stanford’s Institute for Immunity, Transplantation and Infection) unraveled the genetic quirks behind B cells’ ability to recognize a mind-blowingly diverse  set of different pathogens’ and tumor-cells’ characteristic molecular shapes. As a follow-on, Davis and a handful of colleagues – working with what would today be considered the most primitive of molecular-biology tools – isolated the gene underlying the T-cell receptor: an idiosyncratic and very important surface protein that is overwhelmingly responsible for T cells’ recognition of myriad pathogen- and cancer-cell-specific peptide sequences. And they figured out how it works.

The result? (Again from my article:)

With the T-cell receptor gene in hand, scientists can now routinely sort, scrutinize, categorize and utilize T cells to learn about the immune system and work toward improving human health. Without it, they’d be in the position of a person trying to recognize words by the shapes of their constituent letters instead of by phonetics.

Previously: Stanford Medicine magazine traverses the immune systemBest thing since sliced bread? A (potential) new diagnostic for celiac disease, Deja vu: Adults’ immune systems “remember” microscopic monsters they’ve never seen before, Immunology escapes from the mousetrap, Immunology meets infotech and Mice to men: Immunological research vaults into the 21st century
Photo by davidmclaughlin

Aging, Imaging, Ophthalmology, Patient Care, Research, Stanford News

New way to predict advance of age-related macular degeneration

New way to predict advance of age-related macular degeneration

eyeballAge-related macular degeneration, in which the macula – the key area of the retina responsible for vision – begins to degenerate, is the leading cause of blindness and central vision loss among adults older than 65. Some 10-15 million Americans suffer from the disease.

If those numbers don’t scare you, try these: “It affects 14%-24% of the U.S. population aged 65-74 years and 35 -40% of people aged 74 years or more have the disease.” Yow!

Most cases of AMD don’t lead to blindness. But if the disorder progresses to an advanced stage where abnormal blood vessels accumulate underneath the macula and leak blood and fluid, irreversible damage to the macula can quickly ensue if treatment doesn’t arrive right on time.

Timing that treatment just right is a real issue. As I wrote in my recent release about a promising development in this field:

[U]ntil now, there has been no effective way to tell which individuals with AMD are likely to progress to the wet stage. Current treatments are costly and invasive – they typically involve injections of medicines directly into the eyeball – making the notion of treating people with early or intermediate stages of AMD a non-starter. Doctors and patients have to hope the next office visit will be early enough to catch wet AMD at its onset, before it takes too great a toll.

Here’s the good news: A team led by Stanford radiologist and biomedical informatician Daniel Rubin, MD, has found a new way to forecast which patients with age-related macular degeneration are likely to progress to the most debilitating form of the disease – and when.

The advance, chronicled in a study in Investigative Ophthalmology & Visual Science, is a formula – derived from extensive computer analysis of thousands of retinal scans of hundreds of patients’ eyes – that recommends, on a personalized basis,  when to schedule an individual patient’s next office visit in order to optimize the prospect of catching AMD progression before it causes blindness.

The formula predicts, with high accuracy, whether and when a patient with mild or intermediate AMD will progress to the dangerous advanced stage. And it does so simply by crunching imaging data that is already commonly collected in eye doctors’ offices anyway.

“Our technique involves no new procedures in the doctor’s office – patients get the same care they’ve been getting anyway,” Rubin told me. His team just tacked on a sophisticated, computerized image-processing step.

Previously: Treating common forms of blindness using tissue generated with ink-jet printing technology, To maintain good eyesight, make healthy vision a priority and Stanford researchers develop web-based tool to streamline interpretation of medical images
Image courtesy of Daniel Rubin

Aging, Chronic Disease, Clinical Trials, Immunology, Research, Stanford News

Is osteoarthritis an inflammatory disorder? New thinking gets clinical test

Is osteoarthritis an inflammatory disorder? New thinking gets clinical test

SM arthritis imageOsteoarthritis sort of comes with the territory of aging. If you live long enough, you’ll probably get it.

For those fortunate enough not to have a working acquaintance with the disease, I describe its onset in a just-published Stanford Medicine article, “When Bones Collide”:

You start to feel some combination of pain, stiffness and tenderness in a thumb, a knee, a hip, a toe or perhaps your back or neck. It takes root, settles in and, probably, gets worse. And once you’ve got it, it never goes away. Eventually, it can get tough to twist off a bottle cap or to get around, depending on the joint or joints affected.

All too many of us, of course, are perfectly familiar with the symptoms of osteoarthritis. An estimated 27 million people in the United States have been diagnosed with it. By 2030, due mainly to the aging of the population, the number will be more like 50 million. Anything so common is all too easy to look at as inevitable: basically, the result of the same kind of wear and tear on your joints that causes the treads on a commuter car’s set of tires to disappear eventually.

But Stanford rheumatologists Bill Robinson, MD, PhD, and Mark Genovese, MD, think that just may not be the way it works. Almost four years ago I wrote about Robinson’s discovery that osteoarthritis is propelled by a sequence of inflammatory events similar to ones associated with Alzheimer’s disease, cardiovascular disease, and type-2 diabetes. That discovery and a steady stream of follow-up work in his lab have spawned a clinical trial, now underway and led by Genovese, to see if a regimen of anti-inflammatory medicines that’s been shown to roll back osteoarthritis’s progression in mice can do the same thing in people.

That’s the kind of progress most of us could live without.

Previously: New thinking about osteoarthritis, older people’s nemesis and Inflammation, not just wear and tear, spawn arthritis
Illustration by Jeffrey Decoster

Imaging, Immunology, Infectious Disease, Neuroscience, Research, Stanford News

Some headway on chronic fatigue syndrome: Brain abnormalities pinpointed

Some headway on chronic fatigue syndrome: Brain abnormalities pinpointed

patchbrainHow can you treat a disease when you don’t know what causes it? Such a mystery disease is chronic fatigue syndrome, which not so long ago was written off by many physicians as a psychiatric phenomenon because they just couldn’t figure out what else might be behind it. No one was even able to identify an anatomical or physiological “signature” of the disorder that could distinguish it from any number of medical lookalikes.

“If you don’t understand the disease, you’re throwing darts blindfolded,” Stanford neuroradiologist Mike Zeineh, MD, PhD, told me about a week ago. Zeineh is working to rip that blindfold from CFS researchers’ eyes.

From a release I wrote about some breaking CFS research by Zeineh and his colleagues:

CFS affects between 1 million and 4 million individuals in the United States and millions more worldwide. Coming up with a more precise number of cases is tough because it’s difficult to actually diagnose the disease. While all CFS patients share a common symptom — crushing, unremitting fatigue that persists for six months or longer — the additional symptoms can vary from one patient to the next, and they often overlap with those of other conditions.

A study just published in Radiology may help to resolve those ambiguities. Comparing brain images of 15 CFS patients with those from 14 age- and sex-matched healthy volunteers with no history of fatigue or other conditions causing similar symptoms, Zeineh and his colleagues found distinct differences between the brains of patients with CFS and those of healthy people.

The 15 patients were chosen from a group of 200 people with CFS whom Stanford infectious-disease expert Jose Montoya, MD, has been following for several years in an effort to identify the syndrome’s underlying mechanisms and speed the search for treatments. (Montoya is a co-author of the new study.)

In particular, the CFS patients’ brains had less overall white matter (cable-like brain infrastructure devoted to carrying signals rather than processing information), aberrant structure in a portion of a white-matter tract called the right arcuate fasciculus, and thickened gray matter (that’s the data-crunching apparatus of the brain) in the two places where the right arcuate fasciculus originates and terminates.

Exactly what all this means is not clear yet, but it’s unlikely to be spurious. Montoya is excited about the discovery. “In addition to potentially providing the CFS-specific diagnostic biomarker we’ve been desperately seeking for decades, these findings hold the promise of identifying the area or areas of the brain where the disease has hijacked the central nervous system,” he told me.

No, not a cure yet. But a well-aimed ray of light that can guide long-befuddled CFS dart-throwers in their quest to score a bullseye.

Previously: Unbroken: A chronic-fatigue patient’s long road to recovery, Deciphering the puzzle of chronic-fatigue syndrome and Unraveling the mystery of chronic-fatigue syndrome
Photo by Kai Schreiber

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