Functional Characterisation Of Regulators Of Human Globin Gene Switching
Funder
National Health and Medical Research Council
Funding Amount
$232,131.00
Summary
Red blood cells produce haemoglobin, a tetramer of two alpha globin chains and two beta-globin chains. Haemoglobin reversibly interacts with oxygen in such a way that it efficiently shuttles oxygen between the lungs and the rest of the body. Integrity of the hemoglobin molecule, and red cells which carry it, is essential for life of all organisms with blood. The alpha-globin and beta-globin chains that make up haemoglobin are prodcued by red cell precursors in the bone marrow according to the ge ....Red blood cells produce haemoglobin, a tetramer of two alpha globin chains and two beta-globin chains. Haemoglobin reversibly interacts with oxygen in such a way that it efficiently shuttles oxygen between the lungs and the rest of the body. Integrity of the hemoglobin molecule, and red cells which carry it, is essential for life of all organisms with blood. The alpha-globin and beta-globin chains that make up haemoglobin are prodcued by red cell precursors in the bone marrow according to the genetic blueprint (genes) that are inherited. Genetic disorders resulting from defects in the beta-globin gene are the most common inherited disorders of man. Children who fail to make beta-globin have a disease known as beta-thalassaemia. They are transfusion dependent from ~ 6 months of age and need intensive chelation therapy (infusions) to avoid the serious consequnces of iron overload. The average life expectancy in Western cultures is ~ 30 years. There is no cure. In third world countries where a reliable blood supply is unavailable, death occurs earlier. Patients are aften infected with blood born viruses such as hepatitis B, hepatitis C and the AIDS virus, HIV. Sickle cell anaemia is also a very common disease. It is due to a single DNA base mutation at in the beta-globin gene that results in production of normal amounts of a defective beta-globin molecule (HbS). In low oxygen, HbS molecules polymerize in red cells and irreversibly damage them. These red cells get trapped in small blood capillaries throughout the circulation causing small infarcts which results in severe pain and organ damage. The life expectancy is <2 years in the thrid world and ~20-30 years in the west. The irony of these two diseases is that there is a perfectly normal fetal globin gene that has been silenced during fetal life. This grant aims to understand the mechanism of the switch from fetal to adult globin gene usage so it can be reversed in adults with b-thalassemia and sickle cell diseaseRead moreRead less
Hemoglobin is the major protein in red blood cells and is essential for the transport of oxygen from the lungs to the tissues. The disorders of hemoglobin production are the commonest genetic diseases world-wide. These diseases can be markedly improved with elevation of the form of hemoglobin produced by the developing fetus, fetal hemoglobin. We have identified a key factor important for fetal gene expression. We will now determine whether manipulation of this factor can cure hemoglobin disorde ....Hemoglobin is the major protein in red blood cells and is essential for the transport of oxygen from the lungs to the tissues. The disorders of hemoglobin production are the commonest genetic diseases world-wide. These diseases can be markedly improved with elevation of the form of hemoglobin produced by the developing fetus, fetal hemoglobin. We have identified a key factor important for fetal gene expression. We will now determine whether manipulation of this factor can cure hemoglobin disorders.Read moreRead less
A Novel Genetic Element Controlling Adult Hemoglobin Production
Funder
National Health and Medical Research Council
Funding Amount
$493,907.00
Summary
Disorders of the blood protein hemoglobin are the commonest genetic diseases worldwide, and include thalassemia and sickle cell disease. In this proposal we study two novel mouse lines that exhibit thalassemia, but lack any of the known genetic mutations that cause this disease. These mice afford us the opportunity to make unique observations into how hemoglobin is produced, and thereby provide a platform for new therapeutic approaches in these devastating diseases of the blood.
Identification Of Novel Mechanisms Governing Stage-specific Regulation Of The Human Globin Genes
Funder
National Health and Medical Research Council
Funding Amount
$577,889.00
Summary
Hemoglobin is the major protein in red blood cells and is essential for the transport of oxygen from the lungs to the tissues. The disorders of hemoglobin production are the commonest genetic diseases world-wide. These diseases can be markedly improved with elevation of the form of hemoglobin produced by the developing embryo, embryonic hemoglobin. We have identified a key factor important for fetal gene expression. Our goal is to translate these findings into therapies for the globin disorders.
Sickle cell anaemia and ?-thalassaemia are debilitating diseases for which there is no effective treatment. Patients require lifetime blood transfusions and drugs with significant side effects. These diseases are ameliorated in patients that express foetal haemoglobin into adulthood. The goal of this research is to understand how foetal haemoglobin is normally turned off at birth. This will ultimately help us discover how to switch it back on to treat patients.
STUDIES OF NF-E4, A NOVEL FETAL/ERYTHROID SPECIFIC FACTOR INVOLVED IN FETAL GLOBIN GENE REGULATION
Funder
National Health and Medical Research Council
Funding Amount
$753,810.00
Summary
Sickle cell anemia and thalassemia are the commonest genetic disorders worldwide. Those affected suffer devastating clinical sequelae and mortality in the first twenty years of life remains high. A cure for these diseases is dependent on the replacement of the affected or absent hemoglobin protein chains with normally functioning hemoglobins. This is evident in rare patients who co-inherit a natural mutation which elevates fetal hemoglobin (HbF), as these patients have a dramatically ameliorated ....Sickle cell anemia and thalassemia are the commonest genetic disorders worldwide. Those affected suffer devastating clinical sequelae and mortality in the first twenty years of life remains high. A cure for these diseases is dependent on the replacement of the affected or absent hemoglobin protein chains with normally functioning hemoglobins. This is evident in rare patients who co-inherit a natural mutation which elevates fetal hemoglobin (HbF), as these patients have a dramatically ameliorated clinical course. Therefore, treatment strategies which could reactivate fetal globin gene expression after birth should be explored for these diseases. To achieve this goal we must further our understanding of the normal mechanisms of developmental regulation of globin gene expression. To this end we have recently identified a novel gene which is critical for fetal globin expression. The studies we propose here will further define the function of this gene and assess its potential for gene therapy for sickle cell disease and thalassemia.Read moreRead less