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In my life, I’ve seen Christopher Columbus’ reputation take the downward spiral from hero to enemy. It has even affected me in a very superficial manner. See, even though the US government has commemorated the day he found the Americas as a holiday, I remember being devastated the year when my school district decided to nix the day off I was so looking forward too.

Since then, my education in anthropology hasn’t held him to a high standard either. He’s often vilified for starting the end of native American existence. And now a new study in PLoS Neglected Tropical Diseases, traces the emergence of syphilis in Europe to the time when Columbus returned from the Americas. Furthermore, a phylogenetic comparison of the syphlilis causes bacterium, Treponema pallidum, shows that it is a close cousin to the South American tropical disease yaws.

Actually for some time Columbus has been blamed for bringing syphilis to the East. But a skeleton of a man was found in north eastern Britain with signs of bone lesions similar to those causes by syphilis. Preliminary dates of this skeleton suggested that the man had died around 1442, exonerating Columbus for a bit. Here’s a link to that paper, ‘“The syphilis enigma”: the riddle resolved?

Since then, anthropologists re-evaluated the date and suggested that the fishy diet of the region somehow affected the dating technique, making the skeleton seem older than it is. With all this confusion over paleopathology and dating techniques, a genetic analysis of the Trepanoma bacterium seemed much more logical.

In order to conduct the study, 22 human samples, including two Yaws samples, were compared. Even though Yaws is not sexually transmitted (it is transmitted through skin contact), it was included because it is thought that South American variety is a good candidate for the source of the venereal disease. Since the bacteria are so fragile only some sections of the genome could be recovered, including 17 base pairs that ended up being diagnostic of the different Treponema. Through a SNP analysis, it was found that syphilis and South American yaws shared 4 identical base pairs. Not entirely convincing but the overlap with any other kind of Treponema was almost non-existant… A phylogenetic tree of the Treponema samples also showed that syphilis had evolved most recently of the bacterial strains studied, and by most recently we’re talking about 500 or so years ago.

A network path for four informative substitutions shows that New World subsp. pertenue, or yaws-causing strains, are the closest relatives of modern subsp. pallidum strains.

Columbus’ crew is the only one known to have voyaged to the Americas during that time. And the first recorded epidemic of syphilis in Europe broke out among French troops in 1495, two years after Columbus returned from his first voyage across the Atlantic, which points the finger to him and his people. But, with our knowledge of how bacteria can share genes, I’m not entirely convinced it was him. Furthermore, a 4 base homology isn’t a lot.

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