Identification, inheritance, and linkage of B-G-like and MHC class I genesin cranes

We identified B-G-like genes in the whooping and Florida sandhill cranes an d linked them to the major histocompatibility complex (MHC). We evaluated t he inheritance of B-G-like genes in families of whooping and Florida sandhi ll cranes using restriction fragment patterns (RFPs), Two B-G-like genes, d esignated wcbg1 and wcbg2, were located within 8 kb of one another. The ful ly sequenced wcbg2 gene encodes a B-G IgV-like domain, an additional Ig-lik e domain, a transmembrane domain, and a single heptad domain typical of a-h elical coiled coils, Patterns of restriction fragments in DNA from the whoo ping crane and from a number of other species indicate that the B-G-like ge ne families of cranes are large with diverse sequences, Segregation of RFPs in families of Florida sandhill cranes provide evidence for genetic polymo rphism in the B-G-like genes. The restriction fragments generally segregate d in concert with MHC haplotypes assigned by serological typing and by sing le stranded conformational polymorphism (SSCP) assays based in the second e xon of the crane MHC class I genes. This study supports the concept of a lo ngterm association of polymorphic B-G-like genes with the MHC, It also esta blishes SSCP as a means for evaluating MHC genetic variability In cranes.