HAMP and Tangier disease: To consider how MDS with ringed sideroblasts is unique, prior evidence demonstrates that these patients exhibit iron overload prior to the initiation of RBC transfusion (Gattermann, 2005) likely as a consequence of especially suppressed hepcidin relative to other MDS subtypes (Gu et al., 2013; Santini et al., 2011) and HFE gene polymorphisms that predispose to iron overload are detected in up to 21% of MDS with ringed sideroblasts, significantly higher than in other MDS subtypes (Nearman et al., 2007; Valent et al., 2008).