Molecular epidemiologic analysis of Mycobacterium bovis isolates from Mexico.
OBJECTIVE
To assess phylogenetic relationships among Mycobacterium bovis isolates by use of random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) fingerprinting and to relate genetic profiles of isolates to epidemiologic characteristics.


METHODS
400 cattle with tuberculosis.


METHODS
Mycobacterium bovis was isolated from various organs of cattle slaughtered in 6 geographic regions of Mexico. Most cattle were adult Holsteins from large herds that did not participate in a tuberculosis control program. Four random primers and 2 selected primers were used in RAPD-PCR fingerprinting of 88 isolates. Pairwise genetic distance between isolates was obtained and subjected to cluster analysis with bootstrapping to test for levels of support.


RESULTS
98 different fragments were obtained; there was broad genetic diversity among isolates, and each isolate had a unique RAPD-genotype, including those originating from the same herd. Clustering by geographic location, affected organ, or severity of lesion was not detected. Linkage disequilibrium analysis suggested that M. bovis was highly clonal and that mutations develop at a rapid rate among isolates.


CONCLUSIONS
Use of RAPD-PCR could not differentiate M. bovis isolates by epidemiologic characteristics or identify common sources of infection.
Milian-Suazo
F
F
CENID-Microbiología, Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias, Km Palo Alto, DF, México.
Salman
M D
MD
Black
W C
WC
Triantis
J M
JM
Ramirez
C
C
Payeur
J B
JB
Torres
M C
MC
D000818:Animals; D002417:Cattle; D016172:DNA Fingerprinting / Q000662:veterinary; D017931:DNA Primers / Q000737:chemistry; D004269:DNA, Bacterial / Q000032:analysis*; D004587:Electrophoresis, Agar Gel / Q000662:veterinary; D008800:Mexico / Q000453:epidemiology; D009163:Mycobacterium bovis / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D019105:Random Amplified Polymorphic DNA Technique / Q000662:veterinary; D014380:Tuberculosis, Bovine / Q000453:epidemiology* / Q000382:microbiology
D017931:DNA Primers; D004269:DNA, Bacterial