MBE Advance Access originally published online on April 15, 2008
Molecular Biology and Evolution 2008 25(7):1488-1492; doi:10.1093/molbev/msn093
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Research Articles |
High Rates of Molecular Evolution in Hantaviruses




* Department of Biology, Center for Infectious Disease Dynamics, The Pennsylvania State University
LEMB, Institute of Biomedical Science, University of São Paulo, São Paulo, SP, Brazil
School of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil
Fogarty International Center, National Institutes of Health, Bethesda, MD
E-mail: pzanotto{at}usp.br
Accepted for publication April 10, 2008.
Hantaviruses are rodent-borne Bunyaviruses that infect the Arvicolinae, Murinae, and Sigmodontinae subfamilies of Muridae. The rate of molecular evolution in the hantaviruses has been previously estimated at approximately 10–7 nucleotide substitutions per site, per year (substitutions/site/year), based on the assumption of codivergence and hence shared divergence times with their rodent hosts. If substantiated, this would make the hantaviruses among the slowest evolving of all RNA viruses. However, as hantaviruses replicate with an RNA-dependent RNA polymerase, with error rates in the region of one mutation per genome replication, this low rate of nucleotide substitution is anomalous. Here, we use a Bayesian coalescent approach to estimate the rate of nucleotide substitution from serially sampled gene sequence data for hantaviruses known to infect each of the 3 rodent subfamilies: Araraquara virus (Sigmodontinae), Dobrava virus (Murinae), Puumala virus (Arvicolinae), and Tula virus (Arvicolinae). Our results reveal that hantaviruses exhibit short-term substitution rates of 10–2 to 10–4 substitutions/site/year and so are within the range exhibited by other RNA viruses. The disparity between this substitution rate and that estimated assuming rodent–hantavirus codivergence suggests that the codivergence hypothesis may need to be reevaluated.
Key Words: hantavirus nucleotide substitution molecular evolution substitution rates
Peter Lockhart, Associate Editor