Detection of immobilised Murray Valley encephalitis virus RNA using oligonucleotide probes with varying degrees of...

The design of oligonucleotides used for hybridisation studies often utilises available sequence information of the type strain of a particular virus. If hybridisation studies, using such oligonucleotides, are carried out with field isolates of the same virus, the problem of base pair mismatches and consequent difficulties in detection may arise. This study examined the effect of base pair mismatches on the hybridisation between membrane-bound Murray Valley encephalitis virus (MVE) RNA derived from various strains and deliberately mismatched oligonucleotide probes. Under conditions of very low stringency, probes containing up to 5 mismatches were able to detect MVE RNA, but not yeast RNA. Under washing conditions of increased stringency, hybridisation could be detected between MVE virus RNA and probes with only 3 to 4 mismatches. However, the extent of this interaction was dependent on the number and type of mismatches and their relative sequence position.