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People living on the coast of Brazil thousands of years ago carried the bacteria. Endemic Treponema pallidum, a close relative of the microbe responsible for venereal syphilis, cutting-edge DNA research has revealed. The infection likely left the group with mouth sores and sore shins.
Scientists found the microbe’s DNA in 2,000-year-old human skeletons and used it to build the oldest known genome of a relative of syphilis yet discovered. They reported their findings Wednesday (Jan. 24) in the journal. Natureand its discovery delays the origin of the microbe by more than 1,000 years.
The origins of syphilis itself have been debated since an epidemic swept through Europe in 1495. Christopher Columbus and their men were often blamed for bringing the sexually transmitted infection to Europe, but recent research suggests that the disease was on the continent before its transatlantic voyage.
Modern research has also revealed that syphilis is only one of four diseases caused by the same close-knit family of bacteria. The other three “treponemal” diseases (bejel, yaws, and pinta) are not venereal and generally cause chronic infections of the mouth and skin.
Related: Person who had measles 100 years ago helps scientists trace origins of virus
In recent decades, archaeologists in Europe and America have investigated the origins of syphilis and its non-venereal cousins by looking for changes in the bones that are characteristic of the diseases. But until now, they had not found any genetic evidence of these diseases before Columbus’s first voyage to America.
Now, Verena Schünemannpaleogeneticist at the University of Zurich, and his team have discovered DNA from the bacteria Endemic T. pallidum in skeletons from the Jabuticabeira II archaeological site. The site is located near Laguna do Camacho, on the southern coast of Brazil.
More than 200 people were buried at Jabuticabeira II over a period of 1,500 years, from 1200 BC. C. until 400 AD. C., each person huddled together and receiving offerings, such as stone tools, fish and red ocher. TO Previous analysis of the skeletons revealed dozens of cases of bone lesions that suggested a treponemal disease.
To further study these remains, Schünemann and his colleagues examined bone samples from 99 of the skeletons for pathogen DNA. They found that 37 of the skeletons were positive for treponemal DNA. Four of the samples, dating from 350 BC. C. to 573 AD. C., produced enough data for researchers to reconstruct the pathogen’s genome.
“Unexpectedly, these genomes are remarkably similar to those of the causative agent of modern bejel,” the researchers wrote in the study.
Also called endemic syphilis, bejel It is transmitted from person to person through contact with lesions on the skin or mouth. Today, it occurs in hot, arid parts of the eastern Mediterranean and western Asia, not in humid, coastal places like that part of Brazil.
As venereal syphilis, bejel can be treated with antibiotics. But thousands of years ago, Brazil’s indigenous people probably had no effective treatment, meaning they simply lived with the disease.
“There are no historical texts that describe the symptoms people had 2,000 years ago,” Schünemann told LiveScience in an email. However, “the bacteria probably also caused similar skin lesions (to modern bejel).”
Related: ‘Lost’ bacteria found in Neanderthal teeth could be used to develop new antibiotics
None of the people buried at Jabuticabeira II appeared to have been ostracized because of their illness. “Individuals positive for treponemal DNA were not buried separately from other individuals, suggesting that they were treated equally,” the researchers wrote in their study.
The study places Bejel in South America long before European contact in the 15th century, the scientists wrote. It also allowed the researchers to recalculate the bacteria’s probable date of origin, placing it sometime between 780 BC and 780 BC. C. and 450 AD. C., more than a thousand years earlier than previously thought.
Brenda BakerAn anthropologist at Arizona State University who was not involved in the project, told LiveScience in an email that the study’s findings are very interesting and support the hypothesis that treponemal diseases have long existed in the Americas.
“The recovery of such an ancient treponemal genome suggests that we may soon be able to fill huge gaps in our understanding of the evolution and distribution of this pathogen in ancient times as more DNA (ancient DNA) is recovered from other places around the world,” Baker said. .
However, this new date of origin of bejel does not provide clues about the origin of venereal syphilis, Schünemann said.
“Unfortunately, we do not have enough data to be able to say which (T. pale) is the oldest subspecies,” Schünemann said. “More ancient genomes from other subspecies would be needed.”
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