Allelic Variation at the VHa Locus in Natural Populations of Rabbit (Oryctolagus cuniculus, L.)

摘要: The large interallelic distances between the three rabbit Ig V(H)a lineages, a1, a2 and a3, suggest that persistence time of polymorphism could amount to 50 million years, which is much longer than MHC polymorphisms. Rabbit originated in Iberian Peninsula where two subspecies coexist, one confined Southwestern Iberia (Oryctolagus cuniculus algirus). We studied V(H) loci original species range obtain a better understanding evolutionary history this unusual polymorphism. Serological surveys revealed sera from algirus, when tested with locus-specific alloantisera, showed either cross-reactivity ("a-positive" variants) or no reaction at all ("a-blank"). Using RT-PCR, we determined 120 sequences rearranged genes expressed seven algirus rabbits were typed as a-positive a-blank. data show transcribed are closely related V(H)1 alleles domestic rabbits. In contrast, a-blank found preferentially use that, although clearly known genes, define new major allotypic lineage, designated a4. a4 have hallmark residues together number unprecedented amino acid changes framework region 2 3. net protein V(H)a4 V(H)a1, a2, a3 lineages 20, 29, 21% respectively. conclude least four distantly locus exist, seems be endemic range.