Osmotic fragility curves and phthalate density profiles for 4.1^-/-, 4.2^-/-, β-adducin^-/-, and control erythrocytes. (Left) Percentage lysis is plotted compared with osmolarity of incubation medium for 4.1^-/- (•), 4.2^-/- (○), β-addu-cin^-/- (□), and control erythrocytes (▪). (Right) Phthalate density profile for 4.1^-/-, 4.2^-/-, β-adducin^-/-, and control. Symbols are as in panel A. Error bars depict SD.