Using whole genome sequencing to investigate transmission in a multi-host system: bovine tuberculosis in New Zealand
AIM To investigate isolates of Mycobacterium bovis from the Castlepoint area of the Wairarapa using three different methods of DNA typing. METHODS Isolates of M. bovis, obtained from animals in the Castlepoint area between 1982-l 998, were characterised by restriction endonuclease analysis. An isolate representing each restriction type was characterised by two newer DNA typing methods based on the polymorphic GC-rich repetitive sequence (PGRS) and spoligotyping. RESULTS Over 300 isolates were distinguished into 26 restriction types. The 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, indicated that restriction endonuclease analysis was well suited for detailed epidemiological studies at Castlepoint. Spoligotyping was less discriminatory than PGRS typing but both methods could be used to group isolates with different restriction types.