Evolutionary analysis of JC polyomavirus in Misiones' population yields insight into the population dynamics of the early human dispersal in the Americas.

Background: JC polyomavirus (JCV) has an ethno-geographical distribution across human populations.

Objective: Study the origins of the population of Misiones (Argentina) by using JCV as genetic marker.

Methods: Viral detection and characterization was conducted by PCR amplification and evolutionary analysis of the intergenic region sequences.

Results: 22 out of 121 samples were positive for JCV, including 5 viral lineages: MY (n = 8), Eu-a (n = 7), B1-c (n = 4), B1-b (n = 2) and Af2 (n = 1). MY sequences clustered within a branch of Native American origin that diverged from its Asian counterpart about 21,914 years ago (HPD 95% interval 15,383-30,177), followed by a sustained demographic expansion around 5000 years ago.

Conclusions: JCV in Misiones reflects the multiethnic origin of the current population, with an important Amerindian contribution. Analysis of the MY viral lineage shows a pattern consistent with the arrival of early human migrations to the Americas and a population expansion by the pre-Columbian native societies.