GENETIC-ANALYSIS OF THE DIVERSITY AND ORIGIN OF HANTAVIRUSES IN PEROMYSCUS-LEUCOPUS MICE IN NORTH-AMERICA

Nucleotide sequences were determined for the complete M genome segment s of two distinct hantavirus genetic lineages which were detected in h antavirus antibody-and PCR-positive white-footed mice (Peromyscus leuc opus) from Indiana and Oklahoma. Phylogenetic analyses indicated that although divergent from each other, the virus lineages in Indiana and Oklahoma were monophyletic and formed a newly identified unique ancest ral branch within the clade of Sin Nombre-like viruses found in Peromy scus mice. Interestingly, P. leucopus-borne New York virus was found t o be most closely related to the P. maniculatus-borne viruses, Sin Nom bre and Monongahela, and monophyletic with Monongahela virus. In paral lel, intraspecific phylogenetic relationships of P. leucopus were also determined, based on the amplification, sequencing, and analysis of t he DNA fragment representing the replication control region of the rod ent mitochondrial genome. P. leucopus mitochondrial DNA haplotypes wer e found to form four separate genetic clades, referred to here as East ern, Central, North Western, and Southwestern groups. The distinct Ind iana and Oklahoma virus lineages mere detected in P. leucopus of the E astern and Southwestern mitochondrial DNA haplotypes, respectively. Ta ken together, our current data suggests that both cospeciation of Pero myscus-borne hantaviruses with their specific rodent hosts and biogeog raphic factors (such as allopatric migrations, geographic separation, and isolation) have played important roles in establishment of the cur rent genetic diversity and geographic distribution of Sin Nombre-like hantaviruses. In particular, the unusual position of New York virus on the virus phylogenetic tree is most consistent with an historically r ecent host-switching event.