Alpha thalassemia

What is alpha thalassemia? Thalassemia is a blood disorder that is inherited. This means it is passed down from one or both parents through their genes. When you have thalassemia, your body makes less hemoglobin than normal. Hemoglobin is an iron-rich protein in red blood cells. It carries oxygen to all parts of the body. There are two main types of thalassemia: alpha and beta. Different genes are affected for each type. Thalassemia can cause mild or severe anemia. Anemia occurs when your body does not have enough red blood cells or hemoglobin. The severity and type of anemia depends on how many genes are affected. How to say it What causes alpha thalassemia? Alpha thalassemia occurs when one or more of the 4 alpha-globin genes that make up part of the hemoglobin molecule are missing or damaged. There are 4 types of alpha thalassemia: • Alpha thalassemia silent carrier. One gene is missing or damaged, and the other 3 are normal. Blood tests are often normal. Your red blood cells may be smaller than normal. Being a silent carrier means you don’t have signs of the disease, but you can pass the damaged gene on to your child. This is confirmed by DNA tests. • Alpha thalassemia carrier. Two genes are missing. You may have mild anemia. • Hemoglobin H disease. Three genes are missing. This leaves just 1 working gene. You may have moderate to severe anemia. Symptoms can worsen with fever. They can also get worse if you are exposed to certain medicines, chemicals, or infectious age...

This inherited blood disorder usually requires vitamin supplementation. In many cases, people with alpha thalassemia may also need blood transfusions to manage symptoms and maintain good health. Alpha thalassemia is a type of blood disorder in which your body doesn’t produce a normal, healthy amount of the protein hemoglobin. The condition is inherited, meaning it’s passed down from one or both parents. Some forms of alpha thalassemia have no symptoms and require no treatment, while others can lead to problems such as anemia and require medications or even blood transfusions. While there’s currently no cure for alpha thalassemia, proper treatment and a healthy lifestyle may help manage symptoms and allow many people with the disorder to have a normal life expectancy. Alpha thalassemia is one of two main types of The difference between alpha and beta thalassemia is which genes are affected. Hemoglobin is made up of two alpha globin protein chains, which contain four genes (two from each parent) and two beta globin protein chains, which contain two genes (one from each parent). When one or more of the alpha globin protein genes is missing or defective, you’ll have alpha thalassemia. Depending on the number of genes that are affected, a person could have any of four types of alpha thalassemia: • Alpha thalassemia silent carrier: the mildest form, which occurs when only one gene is affected • Alpha thalassemia carrier: an intermediate form of the disorder, which occurs when tw...

Most babies born with Hb Bart syndrome are stillborn or die shortly after birth. In addition, the condition can cause pregnancy complications, including preeclampsia, premature birth, and bleeding. HbH Disease Hemoglobin H (HbH) is the milder form of alpha thalassemia. The symptoms usually appear in early childhood. The condition may cause: • 1 mutated allele: A person is a carrier with no disease symptoms. This is also known as alpha thalassemia silent. • 2 mutated alleles: A person may have mild alpha thalassemia symptoms (known as alpha thalassemia minor or alpha thalassemia trait). • 3 mutated alleles: A person has moderate to severe symptoms (HbH disease). • 4 mutated alleles: A fetus will have Hb Bart syndrome (alpha thalassemia major or hydrops fetalis). This condition is usually fatal before or shortly after birth. Thousands of babies are born with alpha thalassemia every year. It is most prevalent in Asia, Africa, and the Mediterranean area. Approximately 30% of African-Americans have either alpha thalassemia silent or alpha thalassemia trait. Diagnosis Diagnosing alpha thalassemia depends on the severity of the disease.

The thalassemias are a group of inherited hematologic disorders caused by defects in the synthesis of one or more of the hemoglobin chains. Alpha thalassemia is caused by reduced or absent synthesis of alpha globin chains, and beta thalassemia is caused by reduced or absent synthesis of beta globin chains. Imbalances of globin chains cause hemolysis and impair erythropoiesis. Silent carriers of alpha thalassemia and persons with alpha or beta thalassemia trait are asymptomatic and require no treatment. Alpha thalassemia intermedia, or hemoglobin H disease, causes hemolytic anemia. Alpha thalassemia major with hemoglobin Bart's usually results in fatal hydrops fetalis. Beta thalassemia major causes hemolytic anemia, poor growth, and skeletal abnormalities during infancy. Affected children will require regular lifelong blood transfusions. Beta thalassemia intermedia is less severe than beta thalassemia major and may require episodic blood transfusions. Transfusion-dependent patients will develop iron overload and require chelation therapy to remove the excess iron. Bone marrow transplants can be curative for some children with beta thalassemia major. Persons with thalassemia should be referred for preconception genetic counseling, and persons with alpha thalassemia trait should consider chorionic villus sampling to diagnose infants with hemoglobin Bart's, which increases the risk of toxemia and postpartum bleeding. Persons with the thalassemia trait have a normal life expect...