Human transcobalamin isopeptides: Separation by isoelectric focusing and by polyacrylamide gel electrophoresis

Abstract
Transcobalamin was separated by isoelectric focusing and by polyacrylamide gel electrophoresis. Isoelectric focusing showed one band in homozygotes and two bands in heterozygotes, with isoelectric points between 6.3 and 7.0, while polyacrylamide gel electrophoresis produced two and four bands, respectively. Addition of neuraminidase, urea or EDTA had no effect on the separation of transcobalamin at isoelectric focusing. The results obtained by the two methods are comparable and in accord with the nomenclature of transcobalamin variants.