Clinical and Laboratory Investigation of Humans With Informative Iron or Erythroid Phenotypes

This study will examine blood for factors that may cause or prevent diseases involving iron or red blood cells. Iron is an important nutrient for human health that is needed to produce red blood cells. Red blood cells carry oxygen to body tissues. A better understanding of iron and red blood cells may help lead to better treatment of several diseases including anemia. Patients of all ages with red cell abnormalities in the following categories may be eligible for this study: * Diseases with deficiency, overload or maldistribution of iron * Known red blood cell diseases, such as anemias and hemoglobinopathies * Red blood cell diseases of unknown cause, such as hemolysis of unknown cause * Red blood cell abnormalities with no overt clinical disease, such as hereditary persistence of fetal hemoglobin Participants undergo the following procedures: * Medical history * Physical examination * Standard medical tests related to the individual's iron or red blood cell condition Blood draw for the following purposes: * Testing for syphilis and for the hepatitis B and C, HIV, and HTLV-1viruses, and for a pregnancy test for women who can become pregnant * Research purposes. This blood is analyzed for genes, proteins, sugars, and fat molecules.