title: Differentiation of strains in Mycobacterium tuberculosis complex by DNA sequence polymorphisms, including rapid identification of M. bovis BCG.
abstract: The Mycobacterium tuberculosis complex includes M. tuberculosis, M. bovis, M. microti, and M. africanum. Seven strains of the M. tuberculosis complex were sequenced in a region of about 300 bp which contains multiple 15-bp tandem repeats and which is part of a 1,551-bp open reading frame. Four distinct sequences were obtained, each defining a sequevar. A sequevar includes the strain or strains with a given sequence. The type strain M. tuberculosis TMC 102 (H37Rv) was designated sequevar MED-G. When compared to MED-G, sequevar LONG had an insertion of one 15-bp tandem repeat and sequevar SHORT had a deletion of one tandem repeat. Sequevar MED-C had a G-->C substitution, coding for the conservative change Ser-->Thr. BanI cuts only sequevar MED-C at the site of the substitution. PCR-restriction enzyme analysis was used to determine the sequevars of 92 M. tuberculosis complex strains. All 23 M. bovis BCG strains belonged to sequevar MED-C. The M. africanum type strain was sequevar SHORT. The remaining 68 strains of M. tuberculosis, M. bovis (not BCG), and M. microti were sequevars LONG (3 strains) or MED-G (65 strains). PCR-restriction enzyme analysis was applied to reference strains and clinical isolates with a worldwide distribution. This method provides rapid, sensitive, and specific identification of the important vaccine strain M. bovis BCG.
authors.affiliation: Infectious Diseases Section, Durham Veterans Affairs Medical Center, North Carolina 27705, USA.
authors.forename: R
authors.initials: R
authors.lastname: Frothingham
mesh_terms: D000595:Amino Acid Sequence; D001500:BCG Vaccine; D015373:Bacterial Typing Techniques / Q000706:statistics & numerical data; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D009163:Mycobacterium bovis / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction / Q000379:methods / Q000706:statistics & numerical data; D012150:Polymorphism, Restriction Fragment Length; D012091:Repetitive Sequences, Nucleic Acid; D012680:Sensitivity and Specificity; D013045:Species Specificity
chemical_list: D001500:BCG Vaccine; D017931:DNA Primers; D004269:DNA, Bacterial