Differentiation of cytomegalovirus strains by restriction analysis of DNA sequences amplified from clinical specimens.

DNA sequences of 2.0 to 2.7 kb were amplified by polymerase chain reaction from four genes (major immediate-early, DNA polymerase, and glycoproteins B and H) of 20 distinct strains of cytomegalovirus (CMV). Analysis of the unpurified reaction products using selected restriction enzymes showed sufficient diversity of profiles among strains to differentiate all 20. Sequences suitable for restriction analysis were also amplified directly from clinical urine specimens and showed restriction profiles comparable to those of sequences amplified from corresponding CMV culture isolates. Ability to identify specific strains of CMV in amplification products facilitates molecular epidemiologic studies.