Use of IS901 and IS1245 in RFLP typing of Mycobacterium avium complex: relatedness among serovar reference strains, human and animal isolates.
METHODS
Mycobacterium avium complex (MAC) includes major acquired immune deficiency syndrome (AIDS)-associated pathogens. Formerly, MAC serotyping was used for epidemiological purposes. Recently, restriction fragment length polymorphism (RFLP) typing has become available.


OBJECTIVE
Examination of the usefulness of insertion sequence IS1245 in RFLP typing of MAC isolates and the association with IS901 RFLP.


METHODS
Ninety-four serovar reference strains were compared with 144 clinical and animal MAC isolates in RFLP typing.


RESULTS
All but four strains containing M. avium-specific-rRNA possessed IS1245. Most human isolates showed polymorphic multiband IS1245 patterns, which were associated with serovars 4, 6 and 8. Sequential clinical isolates obtained at up to five years' distance displayed indistinguishable/closely related patterns. Eleven M. paratuberculosis isolates showed indistinguishable six-band patterns. All 29 MAC isolates from 23 bird species, 7/23 from mammals and 1/81 clinical isolates showed an IS1245 three-band pattern, associated with serovars 1, 2 and 3. All these IS1245 'bird' type strains showed closely related IS901 RFLPs. Only three IS1245 'non-bird' type strains contained IS901, but exhibited completely different RFLP patterns.


CONCLUSIONS
IS1245-RFLP typing is useful for the classification of M. avium and epidemiology of most human isolates. The highly conserved IS901 and IS1245 RFLPs among 'bird' type isolates provide proof that these strains constitute a separate taxon within the MAC.
Ritacco
V
V
Consejo Nacional de Investigaciones Cientificas y Técnicas, Buenos Aires, Argentina.
Kremer
K
K
van der Laan
T
T
Pijnenburg
J E
JE
de Haas
P E
PE
van Soolingen
D
D
D000818:Animals; D015373:Bacterial Typing Techniques; D001717:Birds / Q000382:microbiology; D004251:DNA Transposable Elements; D006801:Humans; D015269:Mycobacterium avium Complex / Q000145:classification / Q000302:isolation & purification*; D012150:Polymorphism, Restriction Fragment Length
D004251:DNA Transposable Elements