Table 3

Distribution of M. tuberculosis genotypic groups in Houston and the New York City area

PlaceGenotypic group*
1 2 3
Case clusters, no.Unique isolates, no.Case clusters, no.Unique isolates, no.Case clusters, no.Unique isolates, no.
Houston10  (37%)100  (28%)16  (59%)200  (56%)1  (4%)55  (16%)
New York City area7  (32%)23  (23%)15  (68%)63  (62%)015  (15%)
  • * Group 1, allele combination katG codon 463 CTG (Leu) and gyrA codon 95 ACC (Thr); group 2, katG 463 CGG (Arg) and gyrA codon 95 ACC (Thr); group 3, katG 463 CGG (Arg) and gyrA codon 95 AGC (Ser). 

  • Genotypic group 1 versus group 3, P ≈ 0.008; genotypic group 2 versus group 3, P ≈ 0.015; genotypic group 1 versus group 2, not significant. P values were calculated with pooled Houston and New York City area samples.