الفهرس 
ThalassemiasOnly 14 pages are availabe for public view
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Abstract
Recent advances in the understanding of the hemoglobin structure and the genetics of its synthesis has contributed significantly to understanding of hemoglobinopathies. Disorders include those with reduced globin synthesis, abnormal globin chains and failure to switch globin chain synthesis at the appropriate age. This review focused on the clinical features, diagnosis and management strategies of alpha and beta thalassemias, the sickling disorders and touches on a few rarer hemoglobinopathies. The development of PCR and sequencing has revolutionaized the molecular diagnosis of genetic disorders. Although some of recently developed techniques have proven to be robust with high throughput, they are not yet sufficiently sensitive or specific to replace existing conventional PCR based techniques, such as dot blot, ARMS, etc. No single method has the capability to detect each and every mutation, yet the combination of two or more may be sufficient to give a reliable diagnosis (Patrinos et al., 2005). For newborn screening, there is a need for a technique, which is simple, accurate, labor-efficient, and cost effective, and can utilize the original screening sample (dried blood spot). Reverse dot blot and multiplexed ARMS-PCR can be candidate techniques for detecting the known point mutations causing hemoglobinopathies (such as Hb S, C and E), ?-thalassemia, - thalassemia and non deletional HPFH (Bhardwaj et al., 2003). Occasionally, sequencing is also required for the rare or un characterized mutations. Large deletion of the - and ? - globin gene can be identified by gap-PCR directly from dried blood spot. However, unknown deletions may require extensive analysis by traditional southern -blotting (Bhardwaj et al., 2003). Microarray approaches promise improved high-throughput analysis for the future (Clark and Thein, 2004). The prospects for the genetic treatment of the severe hemoglobinopathies have been steadily improving over the past 5 years. The therapeutic efficacy of globin gene transfer has been demonstrated in several mouse models of ?-thalassemia and SCD. As a consequence, research is now focusing on safety issues in anticipation of up coming clinical trials. The concerns regarding use of recombinant lentiviral vectors derived from HIV, and the risk of insertional oncogenesis are in principle eimenable to effective prevention through rational vector design (Sadelain, 2006).