In sickle cell disease (SCD), the β-globin subunit in HbA carries a point variant that results in the formation of an aberrant form termed hemoglobin S. The HBB p.Glu6Val variant in combination with the same or a second HBB disease-associated variant on the second allele leads to SCD, in which erythrocytes are malformed, resulting in chronic hemolytic anemia. The gene discussed is HBB; the disease is Schnyder corneal dystrophy.