Syphilis at the Crossroad of Phylogenetics and Paleopathology

Abstract

The origin of syphilis is still controversial. Different research avenues explore its fascinating history. Here we employed a new integrative approach, where paleopathology and molecular analyses are combined. As an exercise to test the validity of this approach we examined different hypotheses on the origin of syphilis and other human diseases caused by treponemes (treponematoses). Initially, we constructed a worldwide map containing all accessible reports on palaeopathological evidences of treponematoses before Columbus's return to Europe. Then, we selected the oldest ones to calibrate the time of the most recent common ancestor of Treponema pallidum subsp. pallidum, T. pallidum subsp. endemicum and T. pallidum subsp. pertenue in phylogenetic analyses with 21 genetic regions of different T. pallidum strains previously reported. Finally, we estimated the treponemes' evolutionary rate to test three scenarios: A) if treponematoses accompanied human evolution since Homo erectus; B) if venereal syphilis arose very recently from less virulent strains caught in the New World about 500 years ago, and C) if it emerged in the Americas between 16,500 and 5,000 years ago. Two of the resulting evolutionary rates were unlikely and do not explain the existent osseous evidence. Thus, treponematoses, as we know them today, did not emerge with H. erectus, nor did venereal syphilis appear only five centuries ago. However, considering 16,500 years before present (yBP) as the time of the first colonization of the Americas, and approximately 5,000 yBP as the oldest probable evidence of venereal syphilis in the world, we could not entirely reject hypothesis C. We confirm that syphilis seems to have emerged in this time span, since the resulting evolutionary rate is compatible with those observed in other bacteria. In contrast, if the claims of precolumbian venereal syphilis outside the Americas are taken into account, the place of origin remains unsolved. Finally, the endeavor of joining paleopathology and phylogenetics proved to be a fruitful and promising approach for the study of infectious diseases.

Genetic diversity in Treponema pallidum: Implications for pathogenesis, evolution and molecular diagnostics of syphilis and yaws

“…However, evolutionary order with respect to TPA and TPE strains cannot be unambiguously inferred from this analysis (Mulligan et al, 2008), especially in the light of genome decay identified in T. paraluiscuniculi (Šmajs et al, 2011), which suggests that T. paraluiscuniculi is a descendant of an ancestor of pallidum and pertenue strains rather than the opposite. Measurement of evolution rate in treponemes and its comparison with paleopathological evidence and with evolution rates of other bacteria is consistent with the divergence of syphilis from other human treponematoses 5 - 16.5 thousand years ago (de Melo et al, 2010). …”

“…The genetic distance between TPA and TPE strains appears to be inconsistent with a recent emergence of syphilis in the 15 th century and TPA strains appear to be at least several thousand years old (de Melo et al, 2010; Gray et al, 2006). However, one cannot exclude a very rapid adaptation of a parasite to its host under the right circumstances.…”

Syphilis

“…Analyses based on the mutation rates of genomic sequences suggest that the causative agents of yaws and venereal syphilis diverged several thousand years ago from a common progenitor originating in Africa 2 . These estimates argue against the so-called Columbian hypothesis — the notion that shipmates of Christopher Columbus imported a newly evolved spirochete causing venereal syphilis from the New World into Western Europe in the late 15 th century 3 .…”

Nichtvirale sexuell übertragene Infektionen – Epidemiologie, Klinik, Labordiagnostik und Therapie

“…Ausgangspunkt wäre das Gebiet des heutigen Guyana gewesen. Einiges spricht für die Hypothese, dass die Syphilis bereits nach der ersten Besiedlung Amerikas, also 16.500 bis 5000 Jahre vor der heutigen Zeit, aufgetreten ist [12]. Es ist jedoch nach wie vor nicht geklärt, wo der Ursprung der Syphilis zu suchen ist, in oder außerhalb Amerikas?…”