Huntington’s disease (HD) is an inherited degenerative disorder of the central nervous system. Various studies of peripheral tissues from HD patients have led to the assumption that this disease could be the expression of a generalized membrane defect. We have been unable to reproduce fundamental results on which this theory is based, namely differences between electron spin resonance spectra for erythrocytes from diseased and healthy persons. Contradictory results have been published for other methods as well so that it is necessary to rethink the membrane defect theory.