Origins of Syphilis

Carl Zimmer has an article on the Origins of Syphilis in this week's edition of Science.

The basic story is that Kristin Harper, a graduate student at Emory University "and colleagues used the variations in the Treponema DNA to draw an evolutionary tree, the deepest branches belonged to samples of yaws from the Old World. Newer forms of yawslike diseases emerged from the ancestral bacteria. The strange Treponema strain in Guyana sat on a relatively young branch, suggesting that yaws had been carried into the New World by the first immigrants some 12,000 years ago, and that the Guyana strain evolved there. It shares a close ancestry with all strains of syphilis. The relationship also suggests that the Guyana strain is a transitional form that had already acquired some of syphilis's traits, such as the open sores."

I usually refrain from mentioning articles in non-open access publications, but this article contains quotes from Science Blogger John Logsdon, so I include it here. The subject of the article is open-access from PLoS Neglected Tropical Diseases.