Spoligotyping of btb isolates
Microbiology - Vol
61, Iss 1-2 , 15 Mar 1998, pp111-120
Spacer oligotyping of btb isolates compared to typing
by restriction fragment length polymorphism using PGRS, DR and IS6110 probes
Ninety-two Mycobacterium bovis isolates from cattle, deer and badgers in
Northern Ireland and the Republic of Ireland were genotyped by spacer-oligotyping
(spoligotyping) and 67 of these were analysed by restriction fragment length
polymorphism (RFLP). RFLP analysis was performed using three DNA probes, PGRS,
DR and IS6110. Forty-seven of the M. bovis isolates were from 45 different
sources; these were typed using both RFLP and spoligotyping. These 47 isolates
could be differentiated into 24 different RFLP types and 15 distinct
spoligotypes. Although RFLP was found to be more discriminatory compared to the
present spoligotyping technique, spoligotyping was able to differentiate 21 RFLP
type ĎACA' isolates into three different patterns. The remaining 45 M. bovis
isolates were from a small case study, involving infected cattle, deer and
badgers from the same geographic region. All these isolates were analysed by
spoligotyping and a selection of 20 isolates were RFLP typed. All the isolates
in the case study had the same spoligotype pattern with the exception of one
cervine isolate. Similarly all the isolates typed by RFLP had the same pattern.
Consequently, the predominant strain in the case study was not host restricted.
The consistency between the results obtained using the two techniques indicates
the potential value of both techniques for epidemiological studies.
Spoligotyping was found to be a much more rapid technique and easier to perform,
requiring less sophisticated computer software for strain typing. Spoligotyping
results were more readily documented and analysed and the technique was also
more suitable than RFLP analysis for large-scale screening studies.
Mycobacterium bovis; DNA typing; RFLP; Spoligotyping