Evaluation of restriction fragment length polymorphism analysis of the UL10-UL13 genomic region for rapid identification of human cytomegalovirus strains.

A sensitive semi-nested polymerase chain reaction (PCR) was established which allows rapid identification of human cytomegalovirus strains directly on clinical specimens, thereby permitting virus isolation and propagation on cell cultures to be avoided. The assay is based on restriction analysis of PCR products derived from the polymorphic UL10-UL13 region of the human cytomegalovirus genome. The method was evaluated using clinical samples from 23 subjects comprising 16 breast-feeding mothers and seven bone marrow transplantation recipients. For eight mothers, postnatal virus transmission to their offspring via breast milk was studied. Interestingly, for one mother-infant pair, a double infection with two distinct human cytomegalovirus strains could be demonstrated. Stepwise digestion with different restriction enzymes raised the possibility of detecting different strains almost twofold compared to analysis with only one enzyme. This assay is a practical tool for monitoring human cytomegalovirus transmission in various clinical settings.