Poster presentado en 33rd Annual Congress of the European Society of Mycobacteriology

1 de julio de 2012

Rodriguez-Campos S., Romero B., de Juan L., Casal C., Lozano F., Vinolo C., Mateos A., Aranaz A. y Dominguez L.

Spacer oligonucleotide typing (spoligotyping) and Variable Number Tandem Repeat (VNTR) typing are the most widely used molecular techniques for characterisation of Mycobacterium bovis and M. caprae isolates. Spoligotyping targets the Direct Repeat (DR) region which consists of repeated sequences (DRs) interspersed by polymorphic sequences named spacers whose presence or absence of the spacers can be exploited for strain typing. Although 104 spacer sequences have been identified in the DR region, not all of them show reasonable polymorphism to be used for strain typing; today’s standard protocol for spoligotyping is based on 43 spacers. However, the use of the 43 selected spacers might not be appropriate for M. bovis and M. caprae isolates since these spacers were chosen paying particular attention to discrimination of M. tuberculosis. A solution to this problem could be offered by second-generation spoligotyping membranes that compliment the standard membrane to assess further spacers. The discrimination achieved with spoligotyping varies strongly between different countries, e.g. while large population surveys using spoligotyping in mainland Europe, the usefulness of spoligotyping in the British Isles was found to be limited. VNTR typing aims at genetic loci that are distributed all over the genome; these loci contain variable numbers of repeated sequences. Studies in order to determine an ideal set of VNTR markers for M. bovis/M. caprae are less abundant than studies on M. tuberculosis, nevertheless VNTR typing has been used in many countries for epidemiological studies. In Europe, a group of scientists from laboratories investigating bovine tuberculosis have agreed on a consensus of six VNTR loci for the use with M. bovis/M. caprae (ETR-A, ETR-B, ETR-D, QUB11a, QUB11b and QUB3232). In conclusion, when a set of markers is chosen for typing M. tuberculosis, M. bovis or M. caprae we should take into account that due to interspecies variation it might not offer optimised discrimination

	Servicio de Micobacterias (MYC). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM).
	Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM).

Enlace a 33rd Annual Congress of the European Society of Mycobacteriology