Abnormality of erythrocyte membrane protein in a case of congenital stomatocytosis.

A new method of membrane protein analysis was used to demonstrate an erythrocyte membrane protein anomaly. Our approach employed electrofocusing linked to sodiumdodecylsulfate polyacrylamide gel electrophoresis. We observed an aberrant protein, isoelectric at approximately pH 4.5 with an apparent molecular weight of approximately 25,000 in membrane preparations from a patient with congenital stomatocytosis. This protein has not been observed in any healthy donor examined to date.