Issue |
Genet. Sel. Evol.
Volume 36, Number 1, January-February 2004
|
|
---|---|---|
Page(s) | 123 - 137 | |
DOI | https://doi.org/10.1051/gse:2003055 |
DOI: 10.1051/gse:2003055
Estimation of the proportion of genetically unbalanced spermatozoa in the semen of boars carrying chromosomal rearrangements using FISH on sperm nuclei
Alain Pintona, Alain Ducosa and Martine Yerleba 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 March 2003; accepted 23 May 2003)
Abstract
Many chromosomal rearrangements are detected each year in France on young
boars candidates for reproduction. The possible use of these animals
requires a good knowledge of the potential effect of the rearrangements on
the prolificacy of their mates. This effect can be estimated by an accurate
determination of the rate of unbalanced spermatozoa in the semen of boars
which carry the rearrangements. Indeed, these spermatozoa exhibiting normal
fertilizing ability are responsible for an early embryonic mortality, and
then, for a decrease of the litter sizes. The "spermFISH" technique, i.e.
fluorescent in situ hybridization on decondensed sperm heads, has been used on
several occasions in Man, in this perspective. In livestock species, this
method was formerly used mainly for semen sexing purposes. We used it, for
the first time, to estimate the rates of imbalance in the semen of four
boars carrying chromosomal rearrangements: two reciprocal translocations,
rcp(3;15)(q27;q13) and rcp(12;14)(q13;q21), as well as two independent cases
of trisomy 18 mosaicism. The rates of unbalanced gametes were relatively
high for the two reciprocal translocations (47.83% and 24.33%,
respectively). These values differed from the apparent effects of the
rearrangements estimated using a limited number of litters: a decrease in
prolificacy of 23% (estimation obtained using the results of 6 litters)
and 39% (57 litters), respectively for the 3/15 and 12/14 translocations.
The imbalance rates were much lower for the trisomy mosaics (0.58% and
1.13%), suggesting a very moderate effect of this special kind of
chromosomal rearrangement.
Key words: reciprocal translocation / trisomy mosaic / gamete / fluorescent in situ hybridization / chromosome
Correspondence and reprints: a.ducos@envt.fr
© INRA, EDP Sciences 2004