Sickle cell anemia is a heterogeneous disorder with different degrees of clinical severity despite of being caused by a single base pair mutation (Glu6Val) of the ß-globin gene. Understanding this disease will allow us to discover therapies of specific pathophysiological targets. This article reviews some of the factors that can modulate the phenotype of sickle cell anemia, including red blood cell factors and factors extrinsic to the red blood cells.
Sickle cell anemia; modifying factors; epistatic genes; clinical severity