DNA restriction fragments length polymorphism of Mycobacterium tuberculosis isolates in Pisa, Italy.
A total of 60 Mycobacterium tuberculosis strains isolated in the area of Pisa, Italy, over a period from April 1993 to December 1995, were analyzed for the IS6110-based restriction fragments length polymorphism (RFLP). Isolates were found to show a great heterogeneity and only few isolates shared identical DNA banding patterns. In particular, 55 distinct IS6110 patterns were found (average number of isolates per pattern: 1.09) and only 9 strains (15%) occurred in 4 clusters of 2-3 identical clones. Computer analysis of genetic similarities among the strains revealed a family of 17 isolates including the clustered clones implicated in recently acquired infections. No correlation was found between the RFLP DNA patterns of the isolates and drug susceptibility. Of the 5 isolates from immigrants only one showed abnormal DNA fingerprinting. Our data indicate that the patterns of M. tuberculosis isolates in Pisa area are comparable to those of countries with low-prevalence TB and that a low level of TB transmission occurs in this area.
Garzelli
C
C
Department of Biomedicine, University of Pisa, Italy. garzelli@biomed.unipi.it
Lari
N
N
Nguon
B
B
Pistello
M
M
Falcone
G
G
D004269:DNA, Bacterial / Q000235:genetics*; D007558:Italy; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification; D012150:Polymorphism, Restriction Fragment Length
D004269:DNA, Bacterial