Differentiation of mumps vaccine strains from wild viruses by single-strand conformation polymorphism of the P gene.

The DNA fragments amplified through the polymerase chain reaction from part of the P gene of four mumps vaccine strains (Urabe, Torii, Hoshino and Miyahara) were subjected to single-strand conformation polymorphism (SSCP) analysis. These four vaccine strains were differentiated from each other. Furthermore, twelve wild viruses and a laboratory strain (Enders strain) were also distinguished by this method. Viruses isolated from patients who developed aseptic meningitis 4 to 6 weeks after measles-mumps-rubella vaccination showed identical SSCP patterns with the vaccine strain used for immunization. These results were well correlated with sequence analysis of P-gene segments, indicating high applicability of the SSCP analysis for differentiation of mumps vaccine strains not only from each other but from wild viruses.