ANK1 and histiocytic sarcoma: SDS-PAGE allowed the identification and quantification of the major protein constituents of erythrocyte membrane (bands 1–5: α-spectrin, β-spectrin, ankyrin 1, anion exchanger 1, protein 4.1, protein 4.2, protein 4.9 (dematin, protein p55), and actin) and, thus, the identification of the protein membrane deficiency that underlies HS.