High-resolution melt-curve analysis of random amplified polymorphic DNA (RAPD-HRM) for the characterisation of pathogenic leptospires: intra-serovar divergence, inter-serovar convergence, and evidence of attenuation in Leptospira reference collections.
High-resolution melt-curve analysis of random amplified polymorphic DNA (RAPD-HRM) is a novel technology that has emerged as a possible method to characterise leptospires to serovar level. RAPD-HRM has recently been used to measure intra-serovar convergence between strains of the same serovar as well as inter-serovar divergence between strains of different serovars. The results indicate that intra-serovar heterogeneity and inter-serovar homogeneity may limit the application of RAPD-HRM in routine diagnostics. They also indicate that genetic attenuation of aged, high-passage-number isolates could undermine the use of RAPD-HRM or any other molecular technology. Such genetic attenuation may account for a general decrease seen in titres of rabbit hyperimmune antibodies over time. Before RAPD-HRM can be further advanced as a routine diagnostic tool, strains more representative of the wild-type serovars of a given region need to be identified. Further, RAPD-HRM analysis of reference strains indicates that the routine renewal of reference collections, with new isolates, may be needed to maintain the genetic integrity of the collections.
Tulsiani
S M
SM
The University of Queensland, School of Veterinary Science, St. Lucia, Queensland, 4072, Australia. suhella_tulsiani@health.qld.gov.au
Craig
S B
SB
Graham
G C
GC
Cobbold
R C
RC
Dohnt
M F
MF
Burns
M-A
MA
Jansen
C C
CC
Leung
L K-P
LK
Field
H E
HE
Smythe
L D
LD
D000818:Animals; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000032:analysis*; D006801:Humans; D007919:Leptospira / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D007922:Leptospirosis / Q000175:diagnosis / Q000382:microbiology; D051379:Mice; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods*; D051381:Rats; D044366:Transition Temperature
D004269:DNA, Bacterial