Original Article | Open Access
Susan T Howard, Matthew T Oughton, Albert Haddad, Wendy M Johnson, "Absence of the Genetic Marker IS6110 from a Strain of Mycobacterium tuberculosis Isolated in Ontario", Canadian Journal of Infectious Diseases and Medical Microbiology, vol. 9, Article ID 292491, 6 pages, 1998. https://doi.org/10.1155/1998/292491
Absence of the Genetic Marker IS6110 from a Strain of Mycobacterium tuberculosis Isolated in Ontario
A 35-year-old female patient from Waterloo, Ontario was diagnosed with pulmonary tuberculosis in June 1995. Records indicated that the patient had emigrated from Laos circa 1990. A culture grown from a bronchoalveolar lavage specimen was identified as Mycobacterium tuberculosis by standard biochemical methods. Drug-susceptibility testing indicated the strain was resistant to pyrazinamide (PZA), and a mutation was detected within pncA, a gene associated with PZA resistance. Sequence data from the 16S rRNA gene and the 16S/23S rRNA gene spacer confirmed that the strain was a member of the M tuberculosis complex, and analysis of the mpcA and pncA genes supported the identification of the strain as M tuberculosis rather than Mycobacterium bovis. However, the insertion element IS6110, which is used for epidemiological tracing of M tuberculosis, was not detected in this strain by either restriction fragment length polymorphism analysis or by polymerase chain reaction. Two other genetic markers associated with the M tuberculosis complex, IS1081 and the direct repeat element, were present. The arrival of immigrants with tuberculosis from southeast Asia, where most strains of M tuberculosis lacking IS6110 have been traced, has important implications for epidemiological studies of tuberculosis in North America.
Copyright © 1998 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.