Autosomal dominant trait marked by splenomegaly, jaundice, and fragile, spheroid erythrocytes which are prematurely cleared by the spleen; anemia is usually mild; treatment is splenectomy.

Hereditary spherocytosis (HS) is a congenital hemolytic disorder wherein a genetic mutation coding for a structural membrane protein phenotype causes the red blood cells to be sphere-shaped (spherocytosis), rather than the normal biconcave disk shape. This abnormal shape interferes with the cells' ability to flex during blood circulation, and also makes them more prone to rupture under osmotic stress, mechanical stress, or both...