A highly variable genetic disorder affecting the red blood cell membrane and characterized by anemia (q.v.), jaundice (q.v.), enlargement of the spleen, and hemochromatosis (q.v.). HS results from a defect or deficiency in one of the cytoskeletal proteins associated with the erythrocyte membrane. 35%–65% of all HS cases are associated with mutations in the ANK1 gene, and this form of HS is also called ankyrin-1 deficiency, ankyrin-R deficiency, or erythrocyte ankyrin deficiency. Erythrocytes in HS patients are smaller, rounder, and more fragile than normal, get trapped in narrow blood vessels, particularly in the spleen, and hemolyze, resulting in HS symptoms. This disorder is most common in people of northern European ancestry. See ankyrin.
Subjects: Genetics and Genomics.