CLOSE
iStock
iStock

Vikings’ Parasites May Have Led to Lung Problems in Their Modern Descendants

iStock
iStock

Scientists say parasitic worms in the guts of Vikings may have made their modern descendants more vulnerable to asthma, emphysema, and other lung issues. The researchers published their findings last month in the journal Scientific Reports.

While parasites in the ancient world are nothing new, the Vikings’ worms are a relatively new discovery. Last year, scientists examined 1000-year-old poop recovered from a Viking latrine and discovered three different species of intestinal worms.

"Having this extra dimension in our work is extremely exciting for archaeologists," professor and archaeologist Søren Michael Sindbæk told Science Nordic." It means that we can begin to answer questions we couldn't answer before."

He was right. The authors of the new paper say those parasites changed Vikings’ DNA, which changed the DNA of their descendants, predisposing them to lung conditions.

Parasite expert and senior author Richard Pleass and his colleagues were interested in the way antibodies called immunoglobulin E (IgE) are affected by the protein alpha-1-antitrypsin (A1AT).

The researchers collected plasma samples from people currently infected with the parasites, then scanned the plasma, looking for interactions between IgE and A1AT. They found that one specific variant of the A1AT-producing gene was especially helpful in fighting off any diseases the worms might cause. Vikings with this particular gene variant were more likely to live—and more likely to reproduce, passing the gene onto their kin.

Unfortunately, this particular gene variant has more than one effect. Today, people born with this variant are more likely to experience A1AT deficiency, which can predispose them to emphysema, asthma, and chronic obstructive pulmonary disease (COPD). The deficiency is most common in Scandinavians.

“It is only in the last century that modern medicine has allowed human populations to be treated for disease-causing worms,” Pleass said in a press statement. “Consequently, these deviant forms of A1AT, that once protected people from parasites, are now at liberty to cause emphysema and COPD."

A1AT deficiency is treatable, but first you have to find out if you have it. The Alpha-1 Foundation and the World Health Organization recommend genetic testing for anyone with COPD, bronchiectasis, or treatment-resistant asthma.

nextArticle.image_alt|e
Emery Smith
arrow
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."

nextArticle.image_alt|e
iStock
arrow
Health
Just Two Cans of Soda a Day May Double Your Risk of Death From Heart Disease
iStock
iStock

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.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios