Objective: Genetic analysis was performed to infer the relationship between hantaviruses carried by Rattus norvegicus from Henan and Neimenggu provinces and the other known hantavirus and the vaccine strain.
Methods: Total RNA was extracted from lung tissues with Trizol reagent. The complete M and S segment sequences of strains NM133 and Q12 were amplified by RT-PCR. The purified DNA fragments were directly subjected to sequencing, and then to sequence analysis and phylogenetic analysis.
Results: The complete S segment sequences of strains NM133 and Q12 were found to be 1770 nt and 1772 nt in length respectively, with one open reading frame encoding 429 amino acids. The complete M segment sequences of both two strains are 3654 nucleotide in length encoding a protein of 1133 amino acids. The two strains shared a high degree of homology with most of known Seoul virus (SEOV) but quite different from Hantaan virus and other hantaviruses. Furthermore, the nucleoprotein and glycoprotein of the two strains had the congruent structure with the vaccine strain Z37. On the S- and M-phylogenetic trees, both strains (NM133 and Q12) were grouped into the first cluster of SEOV, and were more closely related to the strains, such as: Hb8610, R22, HB55, L99, and K24-e7.
Conclusion: Both strains (NM133 and Q12) belonged to SEOV, and sharing a high degree of homology and similar secondary structure with strains including the vaccine strains Z37, our data suggested that the present vaccine used in China could effectively prevent HFRS caused by SEOV.