Improved sensitivity of restriction endonuclease analysis of herpes simplex virus type 2 DNA with polyacrylamide gradient gel electrophoresis.

Polyacrylamide gradient gel electrophoresis was used to resolve fragments of herpes simplex virus type 2 (HSV-2) DNA, produced by the restriction endonucleases Alu I, Bam HI, Pst I, and Sma I, which cleave the HSV-2 DNA into more than 30 fragments each. HSV-2 strains isolated from different individual patients could be easily distinguished from each other by the endonucleases Bam HI and Sma I. Successive virus isolates from a single person, analyzed using Alu I and Sma I, showed variability of fragment patterns. The effect of passaging the virus in cell cultures for several cycles was evaluated with the restriction endonuclease Alu I. No differences were found after 29 successive passages in VERO cells. Polyacrylamide gradient gel analysis of restriction endonuclease digests of HSV-2 DNA enables the use of enzymes that cleave the DNA into a great number of fragments, thus improving the sensitivity of analysis.