Christopher Columbus' journey to the New World has been genetically linked to the earliest recorded syphilis outbreak in Europe, a study published Monday suggests.
US researchers studied the evolution of Treponema, the family of bacteria that includes syphilis (Treponema pallidum), and they found syphilis is closest in relation to a subspecies of the bacteria in Guyana that causes yaws - typically a childhood disease spread by skin-to-skin contact. The team concluded that yaws was an ancient infection, but venereal syphilis "or a progenitor came from the New World to the Old World and this happened pretty recently in human history," said Kristen Harper, the study's lead author and an evolutionary biologist at Emory University.
Harper believes a nonvenereal form of yaws evolved into sexually transmitted syphilis, though it is unclear how this occurred. "All we can say is the ancestor of syphilis came from the New World, but what exactly it was like, we don't know," she said. "When you put together our genetic data with the epidemic in Naples in 1495, that is pretty strong support for the Columbian hypothesis."
But the study's conclusions rely too much on genetic changes from just two Guyana bacteria strains, Connie Mulligan of the University of Florida and colleagues suggest in a forthcoming editorial. Better evidence would come from DNA extracted from ancient tissue or bones, she said.
"This is a grainy photograph," acknowledged Harper, who added that more research needs to be done.
The full report, "On the Origin of the Treponematoses: A Phylogenetic Approach," was published in Public Library of Science Neglected Tropical Diseases (2008;2(1):e148. doi:10.1371/journal.pntd.0000148)); the related editorial, "Molecular Studies in Treponema Pallidum Evolution: Toward Clarity?," is due to be published in next week's issue.
01/15/08
UNITED STATES: New Study Blames Columbus for Syphilis Spread
Source: Reuters:: Julie Steenhuysen; Courtesy of the CDC National Center for HIV, STD, and TB Prevention