title: Identification and evolution of an IS6110 low-copy-number Mycobacterium tuberculosis cluster.
abstract: A cohort of 56 patients infected with related strains of Mycobacterium tuberculosis, the S75 group, was identified in a New Jersey population-based study of all isolates with a low number of copies of the insertion element IS6110. Genotyping was combined with surveillance data to identify the S75 group and to elucidate its recent evolution. The S75 group had similar demographic and geographic characteristics. Seventeen persons (30%) were linked epidemiologically. The S75 group was segregated from other low-copy-number isolates on the basis of several independent molecular methods. This group included 3 IS6110 genotype variants: BE, H6, and C28, containing 1, 2, and 3 IS6110 insertions, respectively. IS6110 insertion site mapping and comparative sequence analysis strongly suggest a stepwise acquisition of IS6110 elements from BE to H6 to C28. S75 represents a locally produced strain cluster that has recently evolved. The combination of multiple molecular tools with traditional epidemiology provides novel insights into dissemination, local transmission, and evolution of M. tuberculosis.
authors.affiliation: Public Health Research Institute Tuberculosis Center, 455 First Ave., New York, NY 10016, USA. barun@phri.org
authors.forename: Barun
authors.initials: B
authors.lastname: Mathema
authors.forename: Pablo J
authors.initials: PJ
authors.lastname: Bifani
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Driscoll
authors.forename: Lauren
authors.initials: L
authors.lastname: Steinlein
authors.forename: Natalia
authors.initials: N
authors.lastname: Kurepina
authors.forename: Soraya L
authors.initials: SL
authors.lastname: Moghazeh
authors.forename: Elena
authors.initials: E
authors.lastname: Shashkina
authors.forename: Salvatore A
authors.initials: SA
authors.lastname: Marras
authors.forename: Shannon
authors.initials: S
authors.lastname: Campbell
authors.forename: Bonita
authors.initials: B
authors.lastname: Mangura
authors.forename: Kenneth
authors.initials: K
authors.lastname: Shilkret
authors.forename: Jack T
authors.initials: JT
authors.lastname: Crawford
authors.forename: Richard
authors.initials: R
authors.lastname: Frothingham
authors.forename: Barry N
authors.initials: BN
authors.lastname: Kreiswirth
mesh_terms: D004251:DNA Transposable Elements / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D018628:Gene Dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics; D016133:Polymerase Chain Reaction; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000382:microbiology
chemical_list: D004251:DNA Transposable Elements