Analysis of lentiviral genomic variation by denaturing gradient gel electrophoresis

Retroviruses are known for their genetic variability. In any infection, several genotypes usually exist within the host. We have used denaturing gradient gel electrophoresis to study genetic variation of ovine lentiviruses. Starting with viral DNA from cells infected in vitro, a portion of the envelope gene was amplified by PCR, and the products were analyzed by DGGE. With this technique we have been able to detect sequence variations between and within virus isolates and to show evolution of the predominant viral species upon in vivo passage