V-region Genes for Rabbit Ig Heavy Chains

Excerpt

The variable regions of rabbit immunoglobulin (Ig) heavy chains are controlled by three separate but closely linked loci, a, x, and y (V_Ha, V_Hx, and V_Hy) (Oudin 1960a,b; Dray et al. 1963a; Kim and Dray 1972; Mage et al. 1973). The first of these loci to be identified was V_Ha, which has three alleles, a¹, a², and a³. The allotypic specificities a1, a2, and a3, controlled by the V_Ha locus, are found on 65–90% of Ig molecules in normal sera (Dray et al. 1963b; Gilman et al. 1964). The remaining 10–35% of Ig molecules have often been designated “a-negative” molecules. Alloantisera raised against these a-negative molecules identified two additional allotypic specificities x32 and y33 (Knight et al. 1971; Kim and Dray 1972). These specificities, as well as the V_Ha specificities, reside on separate molecules. Genetic studies showed that x32 and y33 were controlled by genes x³² and y³³, which are...