It involves a deficiency of one of the components of hemoglobin, the oxygencarrying molecule in the blood. Haemoglobin f two alpha and two gammaglobin chains is usually also raised. Genetic studies dna analysis to investigate deletions and mutations in the alpha and beta globinproducing gene help in correct diagnosis and improved management in thalassemic patients. Beta thalassemia trait and beta thalassemia disease. Like the silent carrier, alpha thalassemia trait is not a disease and does not affect your health. Alpha thalassemia is a general term for a group of inherited blood disorders characterized by reduced or absent production of alpha globin subunits, resulting in low levels of hemoglobin that is otherwise fully functional. Alpha thalassemia trait causes the size of the red blood cells to be smaller than usual. Alpha thalassemia trait a person with two working copies of the alpha globin gene has alpha thalassemia trait. While the excess beta globin chains are capable of forming soluble homotetramers beta4, hbh, they are. Postnatal stem cell transplantation can be a definitive therapy but has numerous complications.
Knowing the prevalence of thalassemia and the frequency of responsible mutations is therefore an important step. Adult hemoglobin hemoglobin a is made of alpha and beta globins. Both are inherited in an autosomal recessive manner. Two types of alpha thalassemia can cause health problems. Your body makes less of the beta chains, but is still able to make plenty of. In people with the characteristic features of alpha thalassemia, a reduction in the amount of hemoglobin prevents enough oxygen from reaching the bodys tissues. If you need to, you can download the acrobat reader here. Key difference alpha vs beta thalassemia thalassemia is a heterogeneous group of disorders caused by inherited mutations that decrease the synthesis of either alpha or beta globin chains, leading. Detection of common deletional alphathalassemia spectrum by. In people with beta thalassemia, low levels of hemoglobin lead to a lack of oxygen in many parts of the body. Thalassemia omim 141800 is the most common inherited disorder of hemoglobin hb synthesis in the world, with gene frequencies varying between 1% and 98% throughout the tropics and subtropics. The forms of beta thalassaemia with normal haemoglobin a2. Alpha thalassemia normally, alpha globin chain is made by four genes two from each parent, two on each strand of chromosome 16. Beta thalassemia trait when you have one working copy of the beta globin gene and one nonworking copy you have beta thalassemia trait.
Genetic testing to confirm a diagnosis of alpha or beta thalassemia is considered medically. Difference between alpha and beta thalassemia compare. The following are pdf formatted files in various languages. This is called the trans form of alpha thalassemia trait.
Alphathalassemia is one of the most common hemoglobin genetic abnormalities and is caused by the reduced or absent production of the alpha globin chains. There are two different types of alpha thalassemia trait. Alpha thalassemia major atm is usually fatal in utero. The first type of alpha thalassemia trait has one alpha gene missing on each chromosome. Hemoglobin is a protein that carries oxygen to the body. Alphathalassemia is a blood disorder that reduces the bodys production of hemoglobin. Delivery would not be a major problem, and dose titrations may not be too challenging once the pharmacokinetics are determined.
Alpha thalassemia affects the amount of hemoglobin in the red blood cells. In beta thalassemia, the gene for making beta globin chains doesnt work normally. Most beta thalassemia cases result from nucleotide deletions or substitutions. Thalassemia intermedia causes moderate, but variable symptoms which can range from mild to moderate anemia with few other symptoms to anemic conditions that require blood transfusion. Difference between sickle cell anemia and thalassemia. Individuals with beta thalassemia trait or beta thalassemia minor are heterozygous for beta thalassemia, or simply a carrier of beta thalassemia.
Jan 11, 2018 the alpha chain is involved in alpha thalassemia and the beta chain is affected in the more familiar beta thalassemia. Thalassemia can occur in all ethnic groups but is more common in those of southeast asian descent. Beta thalassemie heterozygote pdf beta thalassemias are a group of inherited blood disorders. Newborns need chronic transfusions to replace their red blood cells. Alpha thalassemia alpha thalassemia is due to impaired or absent production of alpha globin chains, which leads to a relative excess of gamma globin chains in the fetus and newborn, and excess beta globin chains in children and adults. Laboratory diagnosis of hemoglobinopathies and thalassemia.
Beta thalassemia is an inherited disease characterized by mild to severe anemia, poor growth, enlargement of the spleen, and skeletal changes. Alpha thalassemia happens when one or more of the genes that control the making of alpha globins is absent or defective. In general, this results in an excess of alpha globins that form insoluble tetrameric inclusions in the red blood cell. The diagnosis of beta thalassaemia can be confirmed by the finding of a compensatory rise in the level of haemoglobin a2 to about 47%, which is the most useful screening test. A total of 6946 subjects were enrolled for evaluating alpha beta thalassemia from 2012 to 2018. They are forms of thalassemia to remove the excess iron. Alpha thalassemia trait alpha thalassemia is common in people of african, southern chinese, southeast asian, middle eastern and mediterranean descent. Beta thalassemia is caused by changes mutations in the hbb gene while alpha thalassemia is caused by mutations in the hba1 andor hba2 genes. If your web browser may not display the document correctly, rightclick over the link and select save as to save it on your computer. Apr 30, 2020 thalassemias are inherited blood disorders. Thalassemia is due to a deficit or absent production of. Both parents must have beta thalassemia trait or another hemoglobin trait for their child to. These family studies suggest that the imbalance observed in thalassemia may be.
Alpha thalassemia nord national organization for rare. Thalasemia beta thalasemia beta terjadi jika terdapat mutasi pada satu atau dua rantai globin. Alpha thalassemia is a blood disorder that reduces the production of hemoglobin. Individuals with thalassemia major have severe anemia and. Thalassemia minor occurs if you receive the faulty gene from only one parent. Alphathalassemia genetic and rare diseases information. Thalassemia is a hereditary blood disorder that results from genetic defects causing deficient synthesis of hemoglobin polypeptide chains. You must inherit the gene defect from both parents to develop thalassemia major. Thalassemia major is a severe form that occurs when no alpha or beta protein is made. Thalassaemia and malaria thalassaemia and malaria 4. Definition beta thalassemia is an inherited red blood cell disorder that results in the complete absence or decreased synthesis of the beta globin chains of hemoglobin.
The synthesis of alpha, beta, and delta peptide chains by reticulocytes from subjects with thalassemia or hemoglobin lepore. Affected people have anemia, which can cause pale skin, weakness, fatigue, and more serious complications. Jul 29, 2015 alpha thalassemia is a blood disorder that reduces the bodys production of hemoglobin. When there is an issue in two chains major thalassemia. People with this form of the disorder are carriers of the disease. There are two major forms of thalassemia as alpha thalassemia and beta thalassemia. Beta thalassemia is a blood disorder that reduces the production of hemoglobin. Alpha thalassemia, the heterozygous state with a single gene for alpha thalassemia, causes no symptoms or merely mild anemia because there is another gene still able to make alpha chains. Thalassemias slide 1 by the end of the lecture, the student.
Thalassemias occur most often among people of italian, greek, middle eastern, southern asian, and african descent. The diagnosis of betathalassaemia can be confirmed by the finding of a compensatory rise in the level of haemoglobin a2 to about 47%, which is the most useful screening test. No restriction needs to be placed on physical activities. Beta thalassemia is a hereditary disease allowing for a preventative treatment by carrier screening and prenatal diagnosis. Beta thalassemia unlike the alpha chain, the production of hemoglobin beta chain is determined by two genes, one from each parent. Thalassemia quantitative a quantitative decrease in the production of alpha or beta globin chain large deletions, point mutations, small insertiondeletion that leads to decreased transcription or an unstable transcript beta thalassemia results from mutations in beta genes pathogenesis a result of the free alpha subunits. While there are many different types of thalassemia, alpha thalassemia and beta thalassemia are the most important because of their potential adverse effects. It can be prevented if one parent has normal genes, giving rise to screenings that empower carriers to select partners with normal hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen to cells throughout the body.
The two main types are called alpha and beta thalassemia, depending on which part of globin. The two main types are called alpha and beta thalassemia, depending on which part of globin chain is produced in reduced amounts victor et al. It is passed down from one or both parents through their genes. Thalassemia genetic and rare diseases information center. Janin ini biasanya mengalami keguguran atau meninggal tidak lama setelah dilahirkan.
Fetal blood transfusions are the only current treatment for supporting the fetus through pregnancy. Other mecha nisms beside imbalanced globin synthesis might influence the. Fiftysix of the patients were followed up with diagnoses of thalassemia major and 11 with thalassemia intermedia. Campbell, md louisiana state university health sciences center, new orleans, louisiana t he thalassemias named from the. Janin yang menderita alpha thalassemia mayor pada awal kehamilan akan mengalami anemia, membengkak karena kelebihan cairan, perbesaran hati dan limpa. Jan 01, 2015 beta thalassemia is caused by changes mutations in the hbb gene while alpha thalassemia is caused by mutations in the hba1 and or hba2 genes. In alpha thalassemia, some of the genes responsible for the coding of the alpha globin chains are deleted.
Get a printable copy pdf file of the complete article 1. However, even in developed countries, most patients with. Thalassemias are a group of inherited blood conditions which result in the impaired production of hemoglobin, the molecule that carries oxygen in the blood. The difference between beta thalassemia minortrait, beta thalassemia major, and beta thalassemia major variations like beta thalassemia intermedia beta thalassemia minortrait is not a disease. The alpha chain is involved in alpha thalassemia and the beta chain is affected in the more familiar beta thalassemia.
Pallor, irritability, growth retardation, abdominal swelling, and jaundice appear during the sec. Persons with beta thalassemia major are diagnosed during infancy. Hemoglobin is the ironcontaining protein in red blood cells that carries oxygen to cells throughout the body. Hba2 is composed of two alpha and two deltaglobin chains. Thalassemia refers to a group of autosomal recessive disorders of haemoglobin manufacturing. It can cause anemia ranging from mild to severe and is most commonly found in people of african, middle eastern, chinese, southeast asian, and, occasionally, mediterranean descent. Although thalassemia mostly affects developing countries, there is limited knowledge of its accurate frequency and distribution in these regions.
Alpha thalassemia is a general term for a group of inherited blood disorders characterized by reduced or absent production of alphaglobin subunits, resulting in low levels of hemoglobin that is otherwise fully functional. Hemoglobin h disease alpha thalassemia information for physicians and other health care providers definition hemoglobin h disease is an inherited hemoglobin disorder in which three of the four alpha globin genes normally present are deleted or have a mutation which impairs alpha globin chain production. Alpha and beta as thalassemia presents with a typical type of anaemia, a simple cbc test with particular attention to a certain parameter such as mch can be the first screening test in pregnancy for carrier status. If you have one, your body makes fewer healthy red blood cells and less hemoglobin. Both alpha and beta thalassemia include the following two forms. Two types of alphathalassemia can cause health problems. Normal hemoglobin consists of two alpha chains and two beta chains. Pdf thalassemia is a globin gene disorder that results in a diminished rate of synthesis of one or more of the globin chains. Started in 1995, this collection now contains 6769 interlinked topic pages divided into a tree of 31 specialty books and 732 chapters.