The etiology of HE includes abnormalities in membrane proteins involved in formation of the membrane structure, including spectrin, protein 4.1 (P4.1), and glycophorin C. HE is basically classified into 5 forms: common HE, spherocytic HE, HPP, SAO, and HE with X chromosome abnormality, based on differences in pathological conditions [9]. The gene discussed is EPB41; the disease is southeast Asian ovalocytosis.