Volume 15, Number 10—October 2009
Research
Discriminatory Ability of Hypervariable Variable Number Tandem Repeat Loci in Population-based Analysis of Mycobacterium tuberculosis Strains, London, UK
Table 3
Discriminatory power of VNTR typing used in the study in establishing true minimum cluster size as marker of real transmission rate*
Genotyping method | No. distinct profiles (variety of types) | No. clusters | Size of clusters, no. isolates | Clustering rate, % (n/N) | Recent transmission rate, % ([n – c]/N) | No. unique isolates |
---|---|---|---|---|---|---|
MIRU15 (n = 2261) | 1,271 | 235 | 2–53 | 54.2 | 44.0 | 1,036 |
MIRU15 + Spoligotyping | 1,619 | 196 | 2–48 | 37.1 | 29.0 | 1,423 |
MIRU15 + VNTR7 | 1,888 | 158 | 2–35 | 22.2 | 17.0 | 1,730 |
*MIRU, mycobacterial interspersed repetitive unit; VNTR, variable number tandem repeats; n, no. clustered cases; N, total no. of strains; c, no. of clusters.