الفهرس 
Acute Lymphoblastic Leukaemia
*Gene polymorphisms in drug metabolic pathwaysOnly 14 pages are availabe for public view
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Abstract
Leukemias are characterized by accumulation of immature abnormal hematopoietic cells in bone marrow and peripheral blood . Acute lymphoblastic leukemia (ALL) is a malignant neoplasm of the lymphocyte precursor cells or lymphoblasts. Leukemic lymphoblasts have exaggerated and uncontrolled growth that fail to mount a normal immune response and cause a DROP in production of normal bone marrow cells. Both T-cell and B-cell precursors can give rise to ALL. B-cell ALL represents about 88% of all cases. CD99 a product of the MIC2 gene is a 32-kDa cell-surface sialoglycoprotein encoded by homologous genes located in the
pseudoautosomal regions of both human sex chromosomes. The antigen is broadly expressed on hematopoietic as well as other cell types, but most intensely in the earliest maturational stages of the
myeloid and the lymphoid lineages. In normal tissues, the expression level of CD99 is particularly high in cortical thymocytes, pancreatic islet cells, granulosa cells of ovary, Sertoli cells of testis and primitive neuroectodermal cells . In addition, CD99 was found to be expressed at high levels in CD34 cells of bone marrow and in all leukocyte lineages, with the highest expression in the most immature lymphocytes and granulocytes .