FIG. 2.

Identification of a new variant of BDV He/80. (A) Samples of total RNA (10 μg) from a standard C6 cell culture persistently infected with BDV He/80 (lane 4) or from newly established persistently infected C6 cell cultures each initially infected with a single He/80-infected C6 cell (lanes 5 to 8) were analyzed by RPA as for Fig. 1, using high concentrations of RNase A. Note the novel signal pattern of the virus in culture 2/1. Undigested RPA probe (lane 1). No specific products were observed when the RPA was carried out with 10 μg of tRNA (lane 2) or 10 μg of total RNA from uninfected C6 cells (lane 3). (B) Fragments of the M-G open reading frames (nt 1975 to 2510) of standard virus (He/80) and variant 2/1 were amplified by RT-PCR, and their sequences were compared. The two T-to-C mutations found in 2/1 (shaded) and the resulting amino acid change in the G open reading frame (I67T [circled]) are indicated.