Evolutionary relationships among strains of Mycobacterium tuberculosis with few copies of IS6110.
Molecular typing of Mycobacterium tuberculosis by using IS6110 shows low discrimination when there are fewer than five copies of the insertion sequence. Using a collection of such isolates from a study of the epidemiology of tuberculosis in London, we have shown a substantial degree of congruence between IS6110 patterns and both spoligotype and PGRS type. This indicates that the IS6110 types mainly represent distinct families of strains rather than arising through the convergent insertion of IS6110 into favored positions. This is supported by identification of the genomic sites of the insertion of IS6110 in these strains. The combined data enable identification of the putative evolutionary relationships of these strains, comprising three lineages broadly associated with patients born in South Asia (India and Pakistan), Africa, and Europe, respectively. These lineages appear to be quite distinct from M. tuberculosis isolates with multiple copies of IS6110.
Dale
Jeremy W
JW
School of Biomedical and Life Sciences, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom. j.dale@surrey.ac.uk
Al-Ghusein
Hasan
H
Al-Hashmi
Salim
S
Butcher
Philip
P
Dickens
Anne L
AL
Drobniewski
Francis
F
Forbes
Ken J
KJ
Gillespie
Stephen H
SH
Lamprecht
Dianie
D
McHugh
Timothy D
TD
Pitman
Richard
R
Rastogi
Nalin
N
Smith
Andrew T
AT
Sola
Christophe
C
Yesilkaya
Hasan
H
D000349:Africa; D001211:Asia, Western; D016000:Cluster Analysis; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics*; D005060:Europe; D019143:Evolution, Molecular; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000145:classification / Q000235:genetics*; D014376:Tuberculosis / Q000382:microbiology*
D004251:DNA Transposable Elements; D004269:DNA, Bacterial