A panel of minisatellite markers for the molecular characterization of Babesia bovis isolates.

GIL G.; MORETTA R.; ECHAIDE I.; MOSQUEDA J.; SUAREZ C.,; FARBER M; WILKOWSKY S.E.

Mérida, México.

Congreso; 9th Biennial Conference of the Society of Tropical Veterinary Medicine; 2007

Society of Tropical Veterinary Medicine

Prevention against babesiosis is currently obtained by vaccination with attenuated strains. When vaccine failuressporadically happens, it would be convenient to differentiate whether they are due to vaccine mishandling or toinfection with Babesia field strains against the vaccinial strains are not protective . Besides, in B. bovis, there is alack of basic knowledge about field strain diversity and geographical strain distribution due to the scarce numberof molecular markers available. Minisatellites are tandem arrays of short repeated units of DNA that are frequentlypolymorphic. Tandem repeat typing is a new generic method which has been proved to be very efficient for thegenotyping of microorganisms using PCR. The purpose of this work was to identify a panel of minisatellites thatcould be applied to the characterization of B. bovis isolates. The Tandem Repeat Finder program was used tosearch for minisatellites through the available sequences from the B. bovis ESTs Sequencing Project. In addition, wechecked the results against the B. bovis genome to discard intron-containing sequences. Four regions harbouringrepeated sequences were chosen and the corresponding primers matching the conserved region were designed.Two of them were the previously described Bv80 and TRAP. The other two were named p200 (according to a relatedantigen reported in B. bigemina) and Anonymous 3. Amplification by PCR, sequencing and comparative analysis of11 strains from Argentina, Brazil, Uruguay, Mexico and USA determined that the tandem repeats varied in numberand sequence among the isolates. Genome analysis of the four markers described in this work revealed that thePCR fragments were single copy and localized in chromosomes 2 and 3. The stability along the time course ofinfection was corroborated for Bv80 and Anonymous 3. Although a large number of field isolates must be tested toassess the feasibility of these methods, the markers proposed in this work could provide new molecular tools forthe genotyping of B. bovis isolates.