Both the clinical course and molecular alterations of sickle cell anemia (Hb SS) are highly distinct. Possible modulators of phenotypical variability have been documented, including alpha-thalassemia and beta S-globin gene cluster haplotypes. (1) The possible benefits of alpha thalassemia co-inheritance also affect hematological parameters. (2) The Hb S intra-cellular concentration seems to pre...

The thalassaemias, the commonest monogenic diseases, are a family of inherited disorders of haemoglobin synthesis characterised by a reduced output of one or other of the globin chains of adult haemoglobin. They are likely to pose an increasing health problem for many developing countries during the early part of the new millennium (1). This review focuses mainly on their control and management...

We have disrupted the 5' locus of the duplicated adult alpha-globin genes by gene targeting in the mouse embryonic stem cells and created mice with alpha-thalassemia syndromes. The heterozygous knockout mice (.alpha/alpha alpha) are asymptomatic like the silent carriers in humans whereas the homozygous knockout mice (.alpha/.alpha) show hemolytic anemia. Mice with three dysfunctional alpha-glob...

In five patients with sickle beta-thalassemia there was balanced alpha- and beta-globin synthesis in the bone marrow and decreased total beta-chain synthesis relative to that of alpha-chain in the peripheral blood. These findings are similar to those in patients with simple beta-thalassemia trait. Despite a range of hemoglobin concentrations from 6.8 to 12.5 g/100 ml in the patients with sickle...

Structural hemoglobin (Hb) variants typically are based on a point mutation in a globin gene that produce a single amino acid substitution in a globin chain. Although most are of limited clinical significance, a few important subtypes have been identified with some frequency. Homozygous Hb C and Hb S (sickle cell disease) produce significant clinical manifestations, whereas Hb E and Hb D homozy...

BACKGROUND In hospital-based studies, alpha(+)-thalassemia has been found to protect against severe, life-threatening falciparum malaria. alpha(+)-Thalassemia does not seem to prevent infection or high parasite densities but rather limits progression to severe disease--in particular, severe malarial anemia. We assessed to what extent alpha(+)-thalassemia influences the association between mild,...

alpha Thalassemia modifies the hematologic expression of homozygous sickle cell (SS) disease, resulting in increased total hemoglobin and HbA2 and decreased HbF, mean cell volume, reticulocytes, irreversibly sickled cells, and bilirubin levels. The age at which these changes develop in children with SS disease is unknown. Ascertainment of globin gene status in a large representative sample of c...

In order to determine the contribution of alpha-thalassemia to microcytosis and hypochromia, 339 adult outpatients seen at Unicamp University Hospital (with the exception of the Clinical Hematology outpatient clinics), who showed normal hemoglobin (Hb) levels and reduced mean corpuscular volume and mean corpuscular hemoglobin, were analyzed. Ninety-eight were Blacks (28.9%) and 241 were Caucasi...