الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The inherited bone marrow failure syndromes are a heterogeneous group of disorders characterized by bone marrow failure usually in association with one or more somatic abnormality. The bone marrow failure (which can involve all or a single cell lineage) often presents in childhood but may not do so until adulthood in some cases. Over the last two decades there have been considerable advances in the genetics of these syndromes with 33 genes having been identified to date. These advances have provided a better understanding of normal hematopoiesis and how this is disrupted in patients with bone marrow failure. Fanconi anemia which is one of these syndromes. The condition is clinically heterogeneous, but characteristic features include the progressive development of bone marrow failure and an increased predisposition to malignancy. Affected individuals may also have one or more developmental abnormality including skin, skeletal, genitourinary, gastrointestinal and neurological anomalies. Approximately 30% of patients with Fanconi anemia have no overt somatic abnormalities. Fanconi anemia cells display a high frequency of spontaneous chromosomal breakage. Diamond-Blackfan anemia usually presents in early infancy, with features of anemia. The hallmark of classical Diamond-Blackfan anemia is a selective decrease in erythroid precursors and normochromic macrocytic anemia associated with a variable number of somatic abnormalities such as craniofacial, thumb, cardiac and urogenital malformations. Severe congenital neutropenia, as its name indicates, is characterized by profound peripheral neutropenia (<0.2×109/L). The disease can progress to myelodysplasia and leukemia. Congenital amegakaryocytic thrombocytopenia usually presents in infancy and is characterized by isolated thrombocytopenia and a reduction or absence of megakaryocytes in the bone marrow, but usually no somatic abnormalities. Approximately 50% of patients develop aplastic anemia, usually by the age of 5 years.