Genet. Sel. Evol. 35 (2003) 685-696
DOI: 10.1051/gse:2003047

Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

Alain Pinton^a, Alain Ducos^a and Martine Yerle<sup>b

a</sup>  UMR INRA-ENVT cytogénétique des populations animales, École nationale vétérinaire de Toulouse, 23, chemin des Capelles, 31076 Toulouse Cedex 3, France
^b  Laboratoire de génétique cellulaire, Institut national de la recherche agronomique, Auzeville BP 27, 31326 Castanet-Tolosan Cedex, France

(Received 12 December 2002; accepted 7 May 2003)

Abstract
A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+) translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5) were elaborated and hybridised independently on chromosomal preparations of the bull who was a carrier of the mosaic translocation. The impossibility of differentiating chromosomes 2 and der(2) from other chromosomes of the metaphases did not allow the production of painting probes for these chromosomes. For all experiments, the quality of painting was comparable to that usually observed with probes obtained from flow-sorted chromosomes. The results obtained allowed confirmation of the interpretations proposed with G-banding karyotype analyses. In the bovine case, however, the reciprocity of the translocation could not be proven. The results presented in this paper show the usefulness of the microdissection technique for characterising chromosomal rearrangements in species for which commercial probes are not available. They also confirmed that the main limiting factor of the technique is the quality of the chromosomal preparations, which does not allow the identification of target chromosomes or chromosome fragments in all cases.

Key words: chromosome / rearrangement / microdissection / cattle / pig / chromosome painting

Correspondence and reprints: Alain Ducos a.ducos@envt.fr

© INRA, EDP Sciences 2003