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The Strength of the Placebo Effect May Hinge on Your DNA

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Whenever medical researchers conduct clinical trials of a new drug, they have to account for the placebo effectthe fact that if you give people a treatment, even if it’s sugar pills, some of them will feel better. Though the treatment might be inactive, patients (and sometimes even the investigators in charge of the study) have an implicit bias toward believing that it works. Whether or not you’re the kind of person who feels better after taking a placebo may have something to do with your genes, though, as a new study from Trends in Molecular Medicine argues. 

Recent research has shown that the placebo effect isn’t just psychological—it’s physiological. Several things happen when you take a placebo, including anxiety reduction, pain suppression, or the activation of reward centers in the brain, which might make you feel better. When you think about it, a placebo can be a beautiful thing. Why wouldn’t you want to feel better without having to pay for real medicine (which might also come with annoying side effects)? 

Hence, it would be nice to be able to figure out who, exactly, is most susceptible to the placebo effect, since not everyone feels great after a course of sugar pills. Led by Kathryn Hall of Harvard Medical School, a group of scientists reviewed previous research for evidence of a genetic variation in the placebo effect by looking for correlations between certain genetic mutations and the strength of a person’s placebo response. Common genetic mutations called Single nucleotide polymorphisms, or SNPs, have been implicated in changing the placebo response in clinical trials. Hall and her team found 11 of these SNPs to be associated with the placebo response in previous research, including those in the dopamine system (the brain’s reward system), the serotonin system (which deals with mood), and the opioid and cannabinoid systems (which both deal with pain). 

With this evidence, it’s looking like the placebo response is even more complicated than we thought. “Given the complex interplay of behavior, expectation, neurotransmitter signaling, disease, and the context of the medical treatment ritual, the molecular pathways and genes involved in contributing to placebo responses is unfolding as a potentially complex network,” the researchers write. 

This study is just a preliminary look into the genetics of placebo responses, but if your response to placebos is coded into your genes, that could affect the reliability of studies that measure a drug’s efficacy against the efficacy of the placebo treatment. If a trial featured all people who respond strongly to placebos in the control group, for instance, the results would skew toward indicating that the drug treatment was completely ineffective. Furthermore, it could lead to honest placebo treatments, where patients knowingly receive placebo treatments (as has been suggested for certain conditions, like Irritable Bowel Syndrome). Because in some cases, feeling better is more important than which medicine you take.  

[h/t: The Economist]

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Emery Smith
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Stones, Bones, and Wrecks
The 'Alien' Mummy Is of Course Human—And Yet, Still Unusual
Emery Smith
Emery Smith

Ata has never been an alien, but she's always been an enigma. Discovered in 2003 in a leather pouch near an abandoned mining town in Chile's Atacama Desert, the tiny, 6-inch mummy's unusual features—including a narrow, sloped head, angled eyes, missing ribs, and oddly dense bones—had both the “It's aliens!” crowd and paleopathologists intrigued. Now, a team of researchers from Stanford University School of Medicine and UC-San Francisco has completed a deep genomic analysis that reveals why Ata looks as she does.

As they lay out in a paper published this week in Genome Research, the researchers found a host of genetic mutations that doomed the fetus—some of which have never been seen before.

Stanford professor of microbiology and immunology Garry Nolan first analyzed Ata back in 2012; the mummy had been purchased by a Spanish businessman and studied by a doctor named Steven Greer, who made her a star of his UFO/ET conspiracy movie Sirius. Nolan was also given a sample of her bone marrow; his DNA analysis confirmed she was, of course, human. But Nolan's study, published in the journal Science, also found something very odd: Though she was just 6 inches long when she died—a typical size for a midterm fetus—her bones appeared to be 6 to 8 years old. This did not lead Nolan to hypothesize an alien origin for Ata, but to infer that she may have had a rare bone disorder.

The current analysis confirmed that interpretation. The researchers found 40 mutations in several genes that govern bone development; these mutations have been linked to "diseases of small stature, rib anomalies, cranial malformations, premature joint fusion, and osteochondrodysplasia (also known as skeletal dysplasia)," they write. The latter is commonly known as dwarfism. Some of these mutations are linked to conditions including Ehlers-Danlos syndrome, which affects connective tissue, and Kabuki syndrome, which causes a range of physical deformities and cognitive issues. Other mutations known to cause disease had never before been associated with bone growth or developmental disorders until being discovered in Ata.

scientist measures the the 6-inch-long mummy called Ata, which is not an alien
Emery Smith

"Given the size of the specimen and the severity of the mutations … it seems likely the specimen was a pre-term birth," they write. "While we can only speculate as to the cause for multiple mutations in Ata's genome, the specimen was found in La Noria, one of the Atacama Desert's many abandoned nitrate mining towns, which suggests a possible role for prenatal nitrate exposure leading to DNA damage."

Though the researchers haven't identified the exact age of Ata's remains, they're estimated to be less than 500 years old (and potentially as young as 40 years old). Genomic analysis also confirms that Ata is very much not only an Earthling, but a local; her DNA is a nearest match to three individuals from the Chilote people of Chile.

In a press statement, study co-lead Atul Butte, director of the Institute for Computational Health Sciences at UC-San Francisco, stressed the potential applications of the study to genetic disorders. "For me, what really came of this study was the idea that we shouldn't stop investigating when we find one gene that might explain a symptom. It could be multiple things going wrong, and it's worth getting a full explanation, especially as we head closer and closer to gene therapy," Butte said. "We could presumably one day fix some of these disorders."

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Health
Just Two Cans of Soda a Day May Double Your Risk of Death From Heart Disease
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If you've been stocking your refrigerator full of carbonated corn syrup in anticipation of warmer weather, the American Heart Association has some bad news. The advocacy group on Wednesday released results of research that demonstrate a link between consumption of sugary drinks—including soda, fruit juices, and other sweetened beverages—and an increased risk of dying from heart disease.

Study participants who reported consuming 24 ounces or more of sugary drinks per day had twice the risk of death from coronary artery disease of those who averaged less than 1 ounce daily. There was also an increased risk of death overall, including from other cardiovascular conditions.

The study, led by Emory University professor Jean Welsh, examined data taken from a longitudinal study of 17,930 adults over the age of 45 with no previous history of heart disease, stroke, or diabetes. Researchers followed participants for six years, and examined death records to determine causes. They observed a greater risk of death associated with sugary drinks even when they controlled for other factors, including race, income, education, smoking habits, and physical activity. The study does not show cause and effect, the researchers said, but does illuminate a trend.

The study also noted that while it showed an increased risk of death from heart disease, consumption of sugary foods was not shown to carry similar risk. One possible explanation is that the body metabolizes the sugars differently: Solid foods carry other nutrients, like fat and protein, that slow metabolism, while sugary drinks provide an undiluted influx of carbohydrates that the body must process.

The news will likely prove troublesome for the beverage industry, which has long contended with concerns that sugary drinks contribute to type 2 diabetes and tooth decay. Some cities, including Seattle, have introduced controversial "soda tax" plans that raise the sales tax on the drinks in an effort to discourage consumption.

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