Human Anelloviruses: Influence of Demographic Factors, Recombination, and Worldwide Diversity
María Cebriá-Mendoza, Beatriz Beamud, Iván Andreu-Moreno, Cristina Arbona, Luís Larrea, Wladimiro Dı́az-Villanueva, Rafael Sanjuán, José M. Cuevas
Abstract
Anelloviruses are the most common human infectious viruses and are considered essentially harmless. Compared to other human viruses, they are characterized by enormous diversity, and recombination is suggested to play an important role in their diversification and evolution. Here, by analyzing the composition of the plasma anellome of 50 blood donors, we find that recombination is also a determinant of viral evolution at the intradonor level. On a larger scale, analysis of anellovirus sequences currently available in databases shows that their diversity is close to saturation and differs among the three human anellovirus genera and that recombination is the main factor explaining this intergenus variability. Global characterization of anellovirus diversity could provide clues about possible associations between certain virus variants and pathologies, as well as facilitate the implementation of unbiased PCR-based detection protocols, which may be relevant for using anelloviruses as endogenous markers of immune status.