Sickle Cell Disease and Sickle Cell Anaemia

Sickle cell haemoglobin (HbS) results from an autosomal recessively inherited mutation in which the 17th nucleotide of the beta globin gene is changed from thymine to adenine and the amino acid glutamic acid is replaced by valine at position 6 in the beta globin chain.[1, 2]Sickle cells have a reduced deformability and are easily destroyed, causing occlusion of the microcirculation and a chronic haemolytic anaemia with a median haemoglobin concentration level of about 9 g/dL.[3] Sickling disorders include heterozygous (AS) sickle cell trait, homozygous (SS) sickle cell disease, compound heterozygous states for HbS with haemoglobins C, D, E, or other structural variants and the combination of the sickle cell gene with different forms of thalassaemia. Sickle cell disease refers to the group of disorders that affects haemoglobin to form abnormal haemoglobin molecules (HbS). Sickle cell anaemia is the name of the specific form of sickle cell disease in which there is homozygosity for the mutation that causes HbS (ie HBSS). Abstract source