For decades leprosyor Hansen’s disease, it was It is considered an imported disease of America after colonial contact with EuropeThe field but a study published in nature Ecology & Evolution completely changes this narrative. A Scientific team achieved Determine the two full genome from Micobacterium lepromatosis, one of the two bacteria that cause leprosyIn human remnants About 4000 years ago in the north Chile. This is the first time that this option is found in archaeological remains, which puts the presence of pathogen in America for millennia to what was considered.
A Skeletons are analyzed belong Two adults man from El -Cherrito and La Erradura depositsIn the Chilean region of Combo. Despite the fact that they represented some inert lesions compatible with infectious processes, it was the genomic analysis of dental and bone tissues that confirmed the presence M. lepromatozThe researchers managed to restore two old old genomes (with coverage up to 74 times), which makes this milestone for bacterial paleogenomy.
Aggressive version with Combian history
Mycobacteria lepromatosis was First described in 2008 And since then he has been Little is present in historical researchThis field is associated with especially serious clinical forms of leprosy, such as Lypromatous scattering of Letra and the phenomenon of Luciocharacterized necrosis, sepsis and extensive skin lesionsIts diagnosis requires certain molecular tools, since the symptoms overlap with the symptoms of M. Leprae, their most famous relative. To date, His presence was documented only in MexicoHe Caribbean pool and southeast Asia, which led to the fact that it was a recent or geographically limited bacteriumField
This new study denies this hypothesisField Detection M. lepromatoz In human remains 4000 years ago, he demonstrates that his story in America is much deeper. Filhenetic analysis This suggests that the very last common ancestor of this bacterium dates back to 26,800 yearsAnd that human strains can begin to diverge from more than 12,000, coinciding with the first movements of the population on the continent after the last glacial maximum. Lepra, in its most severe form, could accompany the first inhabitants of America or was acquired using the type of animal reservoir.
Outside the registration of bones
Until now, the evidence of the LEP in -Colombic America has been scarce and ambiguous. Most of the diagnoses until 1492 were based on non -reversing skeletal lesions. This new job GiveFor the first time, Direct molecular verification of the presence of a disease many centuries before European contactThe researchers note that many ancient infections remained unnoticed if molecular tools, such as paleogemic, which allow you to detect pathogens in contexts, where bone damage is not enough to establish an accurate diagnosis.
This is the presence too reveals the potential of ancient genetics To view the traditional story of the introduction of diseases in America. Lepra was one of the classic examples of pathologies of “brought by Europeans”, but genetic data indicate another story. Hypothesis, what M. lepromatoz It has arisen in America or spreads over millennia between people or wild animals, now charges a new weight. The medical history of the continent is more complicated than we thought.
Rewrite the past to understand this
In addition to its influence on the history of medicine, The study opens up new questions about the relationship between human and animal pathogensThe field is known that M. leprae It can be found in Armadillos and Squirrels, and that these species can act as tanks. Although M. lepromatoz It has not yet been discovered in the wild in South America, the authors of the study protect the monitoring of animals using the approach One health Take into account the connection between the health of humans, animals and the environment.
The authors also emphasize that these results should serve as a starting point for wider research. The possibility that other diseases considered colonial had to -Columbian existence can only be confirmed if molecular methodologies are integrated into archaeological studies. A person remains to maintain more information than can be seen with the naked eye, and it is in their DNA, where part of the story, which we have not yet told, is hidden.
