Comparison of restriction endonuclease profiles of DNA from local herpes simplex virus type 2 (HSV-2) strains

Comparisons of restriction endonuclease profiles of DNA isolated from nine genital HSV-2 strains isolated from 1973 to 1981 were made using six restriction endonucleases (Bgl II, Hind III, Xba 1, Eco RI, Bam HI and Hpa I). The only variation detected in the DNA profiles was found with Eco RI and Bam HI, and in each case all the isolates could be classified into two groups. The difference between the two Eco RI groups could be accounted for by the absence of an Eco RI cleavage site from the HSV DNA. However, if comparison of the profiles of Eco RI and Bam HI cleaved DNA of the individual HSV-2 strains is made then this yields four different groups. The complete Bgl II, Xba I, Eco RI and Hpa I restriction endonuclease maps for the DNA from one isolate (HSV-2M1) are shown. Little variation in the DNA profiles can be found in local genital HSV-2 strains isolated over a 9-year period, when individual restriction enzymes are used. Thus, restriction endonuclease analysis has limited use in local epidemiological studies of genital HSV-2 isolates unless a wide variety of restriction endonucleases are used. However, the technique offers rapid differentiation between HSV-2 and HSV-1 local strains by using Hpa I endonuclease cleavage of HSV DNA.