Hemoglobinopathies are the most common genetic diseases in humans. In sickle cell disease (SCD), a single nucleotide substitution (GTG for GAG, rs334 ) in the sixth codon of the β-globin gene produces an abnormal sickle hemoglobin (HbS). Due to a…
Since it was recognized as the “first molecular disease,” sickle cell anemia (HbSS) caused by homozygosity for the mutant sickle beta-globin gene has provided the classic paradigm for single-gene disorders. Predominant clinical features include hemolytic anemia, episodic painful vasoocclusive events,…
The thalassemia syndromes are a heterogeneous group of inherited anemias which result from defects in the synthesis of one or more of the globin chain subunits of the hemoglobin (Hb) tetramer. The basic defect, decreased or absent production of a…
The term megaloblastic anemia is used to describe a group of disorders characterized by a distinct morphologic pattern in hematopoietic cells. A common feature is a defect in deoxyribonucleic acid (DNA) synthesis, with lesser alterations in ribonucleic acid (RNA) and…
The porphyrias and the sideroblastic anemias are metabolic disorders that involve defects in heme biosynthesis. Most forms of porphyria are inherited in a Mendelian autosomal dominant pattern, but some types are recessive, and others are acquired through exposure to porphyrinogenic…
Anemia of chronic inflammation (ACI) is also termed anemia of chronic disease and considered the second most frequent anemia in the world, after iron deficiency anemia (IDA). ACI is also the most common anemia in hospitalized patients, found in conditions…
Iron is an essential nutrient for every cell of the body. Both decreased and increased total body iron, as well its inappropriate tissue distribution may be clinically important. In iron deficiency, limitation of the synthesis of physiologically active iron-containing compounds…
Iron is an essential trace element required for energy production, oxygen transport and utilization, and cellular proliferation. Iron is a catalyst, acting as an electron donor and an electron acceptor by readily interconverting between ferric (Fe 3+ ) and ferrous…
Anemia is the clinical state of red cell mass inappropriately low for the individual’s physiologic state. Anemias are among the most commonly encountered laboratory findings and clinical disorders in hematology. They encompass a broad range of clinical disorders and diseases…
Anemia, polycythemia, and functional derangements of the human erythrocyte together represent a common group of human disorders with a significant impact on public health. Sickle cell disease, hemoglobin E (HbE)–associated disorders, and the thalassemias are humankind’s most common single-gene diseases,…