Comparison of the physical maps of the DNAs of two cytomegalovirus strains.

The physical maps of the DNAs of two cytomegalovirus isolates, AD169 and SG, were compared by cross-blot hybridization and by hybridization of nitrocellulose-bound SG fragments with cloned 32P-labelled AD 169 fragments. From this comparison it can be concluded that both physical maps are co-linear to a large extent. Most variability existed at the termini of the long and short component (at the repeats). Other differences were the presence or absence of restriction endonuclease cleavage sites.