Molecular typing of Mycobacterium tuberculosis by mycobacterial interspersed repetitive unit-variable-number tandem repeat analysis, a more accurate method for identifying epidemiological links between patients with tuberculosis.
IS6110 fingerprinting of Mycobacterium tuberculosis is the standard identification method in studies on transmission of tuberculosis. However, intensive epidemiological investigation may fail to confirm transmission links between patients clustered by IS6110-restriction fragment length polymorphism (RFLP) typing. We applied typing based on variable numbers of tandem repeats (VNTRs) of mycobacterial interspersed repetitive units (MIRUs) to isolates from 125 patients in 42 IS6110 clusters, for which thorough epidemiological data were available, to investigate the potential of this method in distinguishing epidemiologically linked from nonlinked patients. Of seven IS6110 clusters without epidemiological links, five were split by MIRU-VNTR typing, while nearly all IS6110 clusters with proven or likely links displayed conserved MIRU-VNTR types. These results provide molecular evidence that not all clusters determined on the basis of multibanded IS6110 RFLP patterns necessarily reflect transmission of tuberculosis. They support the use of MIRU-VNTR typing as a more reliable and faster method for transmission analysis.
van Deutekom
Henk
H
Department of Tuberculosis Control, Municipal Health Service, Amsterdam, The Netherlands. hvdeutekom@gggd.amsterdam.nl
Supply
Philip
P
de Haas
Petra E W
PE
Willery
Eve
E
Hoijng
Susan P
SP
Locht
Camille
C
Coutinho
Roel A
RA
van Soolingen
Dick
D
D015373:Bacterial Typing Techniques; D004251:DNA Transposable Elements / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis; D006801:Humans; D020071:Interspersed Repetitive Sequences / Q000235:genetics*; D018598:Minisatellite Repeats / Q000235:genetics*; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length; D014376:Tuberculosis / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission
D004251:DNA Transposable Elements; D004269:DNA, Bacterial