[1] INRA, F-37380 Nouzilly, France
[2] INRA, F-31326 Castanet Tolosan, France
[3] CHU Poitiers, Lab Genet Cellulaire & Mol, F-86000 Poitiers, France
[4] CNRS, ESA 6031, IBMIG, Lab Immunol Mol, F-86000 Poitiers, France
[5] McGill Univ, Dept Biochem, Montreal, PQ H3G 1Y6, Canada
[6] INRA, Stn Ameliorat Genet Animaux Domest, F-31326 Castanet Tolosan, France