CLIA CORN DNA Hb Hb AS Clinical Laboratory Improvement Act Council of Regional Networks for Genetic Services Hemoglobin Hemoglobin A and S (sickle cell trait) NCCLS NIH PKU RNA WIC National Committee for Clinical Laboratory Standards Phenylketonuria Ribonucleic acid Women, Infants, and Children Program Glossary Acute splenic sequestration crisis. The trapping of red cells in the spleen, leading to acute worsening of anemia, splenomegaly, and the potential for shock, vascular collapse, and death. Anemia. Any condition in which there is a reduction of hemoglobin concentration below the normal range; can have many causes other than hemoglobinopathies. Beta-thalassemia trait. A condition in which an individual inherits a normal beta globin gene and a beta globin gene that results in reduced synthesis of normal beta globin. Compound heterozygote. Individual who has inherited two different abnormal genes for a characteristic. Cord blood. Blood from an infant's umbilical cord. Genotype. The genetic composition of an individual. Hand-and-Foot Syndrome. Painful swelling of the hands and feet in patients with sickle cell disease. Hemoglobin. A protein found in red cells that is responsible for the transport of oxygen. The protein consists of two pairs of globin chains with a heme moiety attached to each chain. Hemoglobin AA. The normal hemoglobin genotype. Hemoglobin AS. The hemoglobin genotype of an individual who has inherited a normal beta globin gene from one parent and a beta globin gene from the other parent. This genotype is also known as sickle cell trait. Hemoglobin AC. The hemoglobin genotype of an individual who has inherited a normal beta globin gene from one parent and a beta C globin gene from the other. This genotype also is called hemoglobin C trait. Hemoglobin D, E, G, O. Other abnormal hemoglobins. Hemoglobin F. The predominant hemoglobin found in the fetus. The amount of Hb F decreases after birth and is found in only small amounts in children and adults. Hemoglobin SC. The hemoglobin genotype of an individual with sickle cell disease who has inherited a beta globin gene from one parent and a beta C globin gene from the other. Hemoglobin SS. The hemoglobin genotype of an individual who has inherited a beta globin gene from each parent. Hemoglobinopathy. A generic term for inherited disorders of hemoglobin structure. Heterozygote. Individual who has inherited two different genes for a characteristic. Homozygote. Individual who has inherited the same gene for a characteristic from both parents (these genes may be normal or abnormal). Painful episode. An acute episode of pain affecting one or multiple body sites which occurs in individuals with sickle cell disease. Phenotype. The observed appearance of a characteristic. (This may differ from the genotype.) 66 Sickle beta-thalassemia (S B-thalassemia). A disorder resulting from the inheritance of a sickle (S) gene from one parent and a beta-thalassemia gene from the other. Conditions in this group are also designated as "+" or "o," depending on the severity of the synthetic defect. In the "+" type some normal beta chain is produced. In the "o" type, no normal beta globin is produced. 66 Sickle cell anemia. The hemoglobinopathy resulting from the inheritance of two beta globin genes (SS). Sickle cell disease. A group of diseases characterized by the production of Hb S resulting from the inheritance of two beta globin genes (Hb SS), a beta S and a beta C gene (Hb SC), a beta S and a beta-thalassemia gene (Hb S beta-thalassemia), or a beta S gene and a gene for other abnormal hemoglobin which polymerizes with Hb S. Sickle cell preparation (Metabisulfite). A test that identifies the presence of a sickling hemoglobin. Solubility test. A test using dithionate to identify the presence of sickling hemoglobin. Two-tier-system. A testing strategy where the presence of an abnormal hemoglobin identified by one technique is confirmed by a second test. Unstable hemoglobin. An abnormal hemoglobin that denatures under normal conditions. Biosketches: Sickle Cell Disease Guideline Panel Members Beverly Ames Consumer Representative Mrs. Ames is the parent of a child with sickle cell disease. She has been an advocate for her child at school and in the community, seeking resources which would allow the child to reach his full potential as an individual and enjoy the pleasures of childhood, including summer camp. She was recently a participant in a multidisciplinary conference at Children's Hospital, Washington, DC, on support for children with sickle cell disease. Kwame Anyane-Yeboa, MD Associate Professor of Pediatrics Dr. Anyane-Yeboa is an Associate Professor of Clinical Pediatrics and Genetics at Columbia University and is Director of the Division of Clinical Genetics at the Presbyterian Hospital, New York City. He also has served as President of the New York State Genetics Task Force and is a member of the New York State Sickle Cell Implementation and Advisory Committees. He serves as a consultant in genetics to the Winthrop University Hospital, Harlem Hospital Center, and St Mary's Hospital for Children. He has published articles on the manifestations of various genetic disorders, the prenatal diagnosis of hemoglobinopathies, and the implementation and evaluation of newborn screening programs. Samuel Charache, MD Professor, Departments of Medicine and Pathology Johns Hopkins University Dr. Charache is a Professor of Medicine and Pathology at The Johns Hopkins University School of Medicine. He also serves as Director of the Hematology Division, Department of Laboratory Medicine at Johns Hopkins Hospital. He has long been interested in hemoglobinopathies and has published numerous papers describing the laboratory and clinical aspects of newly identified hemoglobins and the pathogenesis and clinical manifestations of sickle cell disease. Dr. Charache has served as a member of the hematology study section of the National Institutes of Health, as a consultant to the Sickle Cell Disease Branch, NIH, as chairman of the Blood Diseases and Resources Committee of the National Heart, Lung, and Blood Institute, and as chairman of the American Society of Hematology Committee on Clinical Laboratory Standards, as well as the Society's representative to the National Committee on Clinical Laboratory Standards. |