[Spectrin extractabilities from erythrocyte membranes in patients with myotonic dystrophy]

Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, spectrin extractabilities (SE) were determined after spectrins were removed from erythrocyte membranes by low ionic strength and chelating agent. The SE from red cell membranes was significantly reduced with respect to matched controls in 13 myotonic dystrophy patients, 81.3 +/- 7.2% and 54.2 +/- 9.1% (m +/- SD), respectively (P less than 0.01). There were no significant differences between the patients and controls in molecular weights and amounts of spectrin as well as Band3 protein. Our results are consistent with the concept of membrane defect affecting erythrocytes in this disorder.