Human JCV Infections as a Bio-Anthropological Marker of the Formation of Brazilian Amazonian Populations

Abstract

JC polyomavirus (JCV) is a member of the Polyomaviridae family. It presents a tropism to kidney cells, and the infection occurs in a variety of human population groups of different ethnic background. The present study investigated the prevalence of JCV infection among human populations from the Brazilian Amazon region, and describes the molecular and phylogenetic features of the virus. Urine samples from two urban groups of Belém (healthy subjects), one Brazilian Afro-descendant “quilombo” from the Rio Trombetas region, and native Indians from the Wai-Wai, Urubu-Kaapor, Tembé, Assurini, Arara do Laranjal, Aukre, Parakanã, Surui and Munduruku villages were investigated for the presence of the virus by amplifying VP1 (230 bp) and IG (610 bp) regions using a polymerase chain reaction. Nucleotide sequences (440 nucleotides, nt) from 48 samples were submitted to phylogenetic analysis. The results confirmed the occurrence of types A (subtype EU), B (subtypes Af-2, African and MY, Asiatic) and C (subtype Af-1) among healthy subjects; type B, subtypes Af-2 and MY, among the Afro-Brazilians; and type B, subtype MY, within the Surui Indians. An unexpected result was the detection of another polyomavirus, the BKV, among Afro-descendants. The present study shows, for the first time, the occurrence of JC and BK polyomaviruses infecting humans from the Brazilian Amazon region. The results show a large genetic variability of strains circulating in the region, infecting a large group of individuals. The presence of European, Asiatic and African subtypes associated to the ethnic origin of the population samples investigated herein, highlights the idea that JCV is a fairly good marker for studying the early migration of human populations, reflecting their early and late history. Furthermore, the identification of the specific mutations associated to the virus subtypes, suggests that these mutations have occurred after the entrance of the virus in the Amazon region of Brazil.

Complex virome in feces from Amerindian children in isolated Amazonian villages

“…The founding native American population is estimated to have had a small effective population size 6 and migration from the Bering strait may have occurred in one major or multiple waves 7 – 10 . Serological and PCR tests have shown that chronic viral infections such as Human T-lymphotropic Virus 2 (HTLV2), JC polyomavirus (JCV), and Human herpesvirus 8 (HHV8), may have been introduced during the continent’s initial human colonization, while other subtypes of HTLV2 and JCV were likely introduced later during the slave trade into Brazil 11 – 13 . Coincident with mixing of Amerindian and later immigrant populations in urban settlements, native populations underwent strong population bottlenecks believed to be coincident with imported airborne epidemics such as small pox, measles, and more recently influenza, to which they may have been particularly susceptible due to lack of prior exposure 14 , 15 .…”

Infectious Agents As Markers of Human Migration toward the Amazon Region of Brazil

“…The initial approach to investigate JC virus (JCV) in the Brazilian Amazon involved 10 native Indian tribes from the States of Para (Wai-Wai, Munduruku, Kendjam, Arara Laranjal, Parakana, Aukre, Tembe, and Assurini), Maranhao (Urubu-Kaapor), and Rondonia (Surui), one Brazilian afro-descendant “quilombo” from the Rio Trombetas region in the West of the State of Para and from its capital, the city of Belem ( Figure 1 ). JC virus was detected in urine samples using the amplification of vp1 gene and IG region according to a previously described protocol ( Cayres-Vallinoto et al, 2012 ). The amplified products of the IG region were used to construct the phylogenetic trees and subsequent relationships among the strains detected.…”

“…The amplified products of the IG region were used to construct the phylogenetic trees and subsequent relationships among the strains detected. Detailed methodological steps were previously described ( Cayres-Vallinoto et al, 2012 ).…”

“…The finding of polyomavirus infections in the Amazon region helped to show the close association of migration routes of viruses and humans during their migration pathways. JC virus was described in the following communities: types A (subtype EU), B (subtypes Af-2, African and MY, Asiatic), and C (subtype Af-1) among subjects living in Belem; type B, subtypes Af-2 and MY, among Afro-Brazilians; and type B, subtype MY, within the Surui Indians ( Figure 6 ; Cayres-Vallinoto et al, 2012 ).…”

“… Phylogenetic tree showing JCV subtypes isolated from Amazon populations. [adapted from Cayres-Vallinoto et al (2012) ]. …”