SPTA1 and histiocytic sarcoma: HS is caused by mutations in various erythrocyte membrane protein genes, including ANK1 (ankyrin), SPTB (β-spectrin), SLC4A1 (Band 3), SPTA1 (α-spectrin), and EPB42 (protein 4.2) with significant heterogeneity in the molecular deficiency (He et al., 2018).