Complexity of the genetic control of a structural marker in the CH1 homology region of pig IgG.
The occurrence of two variant peptides P1 and P2 originating in the vicinity of the heavy-light chain disulphide bridge in the CH1 homology region was examined in IgG samples prepared from 36 randomly selected pigs. The peptides labelled with 35S at the half-cystine residues were separated on two-dimensional peptide maps and their ratio was quantitatively evaluated by a non-destructive automated method using semiconductor detectors. Fourteen individuals were found to yield only the peptide P1, the remaining 22 individuals yielded both P1 and P2 with a mean ratio of 69.4: 30.6. A model of genetic determination of the amino acid interchange, serine-leucine, distinguishing the peptides P1 and P2 was suggested. It has been assumed that the gene for one gamma-chain subclass exists only in the form coding for the peptide P1 whereas the gene for another gamma-chain subclass exists in two allelic forms coding for either P1 or P2.
D000818:Animals; D004220:Disulfides / Q000032:analysis; D007141:Immunoglobulin Fc Fragments / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis / Q000235:genetics*; D010446:Peptide Fragments / Q000032:analysis*; D011110:Polymorphism, Genetic; D013552:Swine
D004220:Disulfides; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D010446:Peptide Fragments