Hemoglobinopathies
Hemoglobins, Abnormal
Hemoglobin C
A commonly occurring abnormal hemoglobin in which lysine replaces a glutamic acid residue at the sixth position of the beta chains. It results in reduced plasticity of erythrocytes.
Hemoglobin E
Thalassemia
beta-Thalassemia
A disorder characterized by reduced synthesis of the beta chains of hemoglobin. There is retardation of hemoglobin A synthesis in the heterozygous form (thalassemia minor), which is asymptomatic, while in the homozygous form (thalassemia major, Cooley's anemia, Mediterranean anemia, erythroblastic anemia), which can result in severe complications and even death, hemoglobin A synthesis is absent.
Premarital Examinations
Anemia, Sickle Cell
Hemoglobin A2
An adult hemoglobin component normally present in hemolysates from human erythrocytes in concentrations of about 3%. The hemoglobin is composed of two alpha chains and two delta chains. The percentage of HbA2 varies in some hematologic disorders, but is about double in beta-thalassemia.
Fetal Hemoglobin
The major component of hemoglobin in the fetus. This HEMOGLOBIN has two alpha and two gamma polypeptide subunits in comparison to normal adult hemoglobin, which has two alpha and two beta polypeptide subunits. Fetal hemoglobin concentrations can be elevated (usually above 0.5%) in children and adults affected by LEUKEMIA and several types of ANEMIA.
alpha-Thalassemia
Hemoglobin H
An abnormal hemoglobin composed of four beta chains. It is caused by the reduced synthesis of the alpha chain. This abnormality results in ALPHA-THALASSEMIA.
Hemoglobin, Sickle
An abnormal hemoglobin resulting from the substitution of valine for glutamic acid at position 6 of the beta chain of the globin moiety. The heterozygous state results in sickle cell trait, the homozygous in sickle cell anemia.
Hemoglobin SC Disease
One of the sickle cell disorders characterized by the presence of both hemoglobin S and hemoglobin C. It is similar to, but less severe than sickle cell anemia.
Hemoglobin C Disease
alpha-Globins
Members of the alpha-globin family. In humans, they are encoded in a gene cluster on CHROMOSOME 16. They include zeta-globin and alpha-globin. There are also pseudogenes of zeta (theta-zeta) and alpha (theta-alpha) in the cluster. Adult HEMOGLOBIN is comprised of 2 alpha-globin chains and 2 beta-globin chains.
Globins
Hemoglobin A
Erythrocyte Indices
Priapism
Hemoglobins
The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.
Pregnancy Complications, Hematologic
Prenatal Diagnosis
Health Fairs
Genetic Counseling
An educational process that provides information and advice to individuals or families about a genetic condition that may affect them. The purpose is to help individuals make informed decisions about marriage, reproduction, and other health management issues based on information about the genetic disease, the available diagnostic tests, and management programs. Psychosocial support is usually offered.
Neonatal Screening
The identification of selected parameters in newborn infants by various tests, examinations, or other procedures. Screening may be performed by clinical or laboratory measures. A screening test is designed to sort out healthy neonates (INFANT, NEWBORN) from those not well, but the screening test is not intended as a diagnostic device, rather instead as epidemiologic.
Erythrocytes
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
Fetal Blood
Chromatography, High Pressure Liquid
Blood Transfusion
Electrophoresis, Capillary
Erythroid Precursor Cells
The cells in the erythroid series derived from MYELOID PROGENITOR CELLS or from the bi-potential MEGAKARYOCYTE-ERYTHROID PROGENITOR CELLS which eventually give rise to mature RED BLOOD CELLS. The erythroid progenitor cells develop in two phases: erythroid burst-forming units (BFU-E) followed by erythroid colony-forming units (CFU-E); BFU-E differentiate into CFU-E on stimulation by ERYTHROPOIETIN, and then further differentiate into ERYTHROBLASTS when stimulated by other factors.