DNA typing of Mycobacterium bovis strains from the Castlepoint area of theWairarapa

Aim. To investigate isolates of Mycobacterium bovis from the Castlepoint ar ea of the Wairarapa using three different methods of DNA typing. Methods. Isolates of M. bovis, obtained from animals in the Castlepoint are a between 1982-1998, were characterised by restriction endonuclease analysi s. An isolate representing each restriction type was characterised by two n ewer DNA typing methods based on the polymorphic GC-rich repetitive sequenc e (PGRS) and spoligotyping. Results. Over 300 isolates were distinguished into 26 restriction types. Th e 24 available restriction types were differentiated into 11 PGRS types and 7 spoligotypes. The three most common restriction types had the same PGRS type and the same spoligotype. Conclusions. The relatively large number of restriction types found, indica ted that restriction endonuclease analysis was well suited for detailed epi demiological studies at Castlepoint. Spoligotyping was less discriminatory than PGRS typing but both methods could be used to group isolates with diff erent restriction types.