FIG. 2.

HHV-6 RT-PCR results. Results of ethidium bromide staining of agarose gel electrophoresis of specimens obtained from representative patient samples are shown. (A) Lanes 1 to 6, RT-PCR of specimens from children with acute HHV-6 infection (defined as isolation of HHV-6 in culture, a positive DNA PCR, and a negative antibody titer). Lane 6 demonstrates the negative RT-PCR result from a specimen from one of these children. Arrowhead, 500 bp. (B) Corresponding histidyl-tRNA synthetase RT-PCR of samples in panel A. Arrowhead, 237 bp. (C) Lanes 1 to 7, RT-PCR of samples from children with prior HHV-6 infection (negative HHV-6 culture, positive DNA PCR, and negative RT-PCR). (D) Corresponding histidyl-tRNA synthetase RT-PCR of samples in panel C. (E) Lanes 1 to 7, RT-PCR of samples from children with no evidence of prior infection with HHV-6 (negative HHV-6 culture and negative DNA PCR). Lane 7 demonstrates the positive RT-PCR result from a sample from one child. (F) Corresponding histidyl-tRNA synthetase RT-PCR of samples in panel E. M, marker with 123-bp ladder; +, positive control; −, negative control.