Thalassemia is an inherited blood disorder that reduces the production of functional hemoglobin the protein in red blood cells that carries oxygen. Alpha thalassemia is a blood disorder that reduces the production of hemoglobin. Your body makes less of the beta chains, but is still able to make plenty of. A case of nonbetaglobin gene linked beta thalassaemia in a dutch family with two additional alphagene defects. The presence of sickle cell trait with beta thalassemia is a major hemoglobinopathy and results in manifestations of sickle cell. Over two million people in the united states carry the genetic trait for thalassemia. Thalassemia is a treatable disorder that can be wellmanaged with blood transfusions and chelation therapy. Clinical signs were compatible with severe microcytic anemia requiring bimonthly blood transfusions.
In people with the characteristic features of alpha thalassemia, a reduction in the amount of hemoglobin prevents enough oxygen from reaching the bodys tissues. Thalassemias occur most often among people of italian, greek, middle eastern, southern asian, and african descent. The different types of betathalassemia mutation produce clinical and hematological phenotypes of variable severity even in betacarriers the identi. Alpha thalassemia major with hemoglobin barts usually results in fatal hydrops fetalis. In alpha thalassemia, the severity of thalassemia you have depends on the number of gene mutations you inherit from your parents. Laboratory diagnosis of thalassemia brancaleoni 2016. The red blood cell count rbc and the derived indices are extremely. There are two main types, alpha thalassemia and beta thalassemia. Carrier frequencies of betathalassemia vary from 1% to.
In people with beta thalassemia, low levels of hemoglobin lead to a lack of oxygen in many parts of the body. Jan 11, 2018 the alpha chain is involved in alpha thalassemia and the beta chain is affected in the more familiar beta thalassemia. Betathalassemia is caused by reduced or absent synthesis of the betaglobin chains of the adult hemoglobin tetramer hba, which is made up of two. Alpha thalassemia trait is an inherited abnormality of hemoglobin that results in a very mild anemia low blood hemoglobin level and smaller size of the red blood cells reduced mcv. Dont think there is enough info to know how the different levels trait vs. Carrier frequencies of beta thalassemia vary from 1% to 5% while prevalence data for alpha thalassemia are scant. Alpha thalassemia intermedia, or hemoglobin h disease, causes. Individuals who have one abnormal beta globin gene. Genetic studies dna analysis to investigate deletions and mutations in the alpha and betaglobinproducing gene help in correct diagnosis and improved management in thalassemic patients. Alpha globin is made by four genes, two on each strand of chromosome 16.
Coinheritance of alphathalassemia, which may normalize the rbc indices. Alpha thalassemia normally, alpha globin chain is made by four genes two from each parent, two on each strand of chromosome 16. A quantitative decrease in the production of alpha or beta globin chain. Normally, people have 4 genes for alpha globin with 2 genes on each chromosome aaaa. Beta thalassemia trait when you have one working copy of the beta globin gene and one nonworking copy you have beta thalassemia trait. There are two main types of thalassemia, alpha thalassemia and beta thalassemia. However, in alphabeta double heterozygotes, the hba2 concentration remains in the betathalassemia carrier range and thus is diagnostic. Alpha thalassemia thal uh see mee uh trait is a condition that affects the amount of hemoglobin in the red blood cells. Alphathalassaemia is a group of disorders of haemoglobin synthesis, caused by mutations or deletions in at least 1 of the 4 alphaglobin genes, leading to variably impaired alphaglobin chain production, with accumulation of the now excess and unpaired betaglobin chains. Alpha thalassemia trait all red blood cells contain hemoglobin hee muh glow bin, which carries oxygen from your lungs to all parts of your body. A trait carrier of thalassemia will always be a trait carrier. The alpha chain is involved in alpha thalassemia and the beta chain is affected in the more familiar beta thalassemia.
Here is an article about a region of italy historically associated with thalassemia and malaria may have been protected from covid19. The two main types are called alpha and beta thalassemia depending on which part. Over 200 mutations in the beta globin gene and 70 mutations in the alpha globin gene have been. Hemoglobin is the protein in red blood cells that carries oxygen to cells throughout the body. Alpha thalassemia trait causes the size of the red blood cells to be smaller than usual. It is commonly mistaken for iron deficiency which also causes anemia.
Over 200 mutations in the betaglobin gene and 70 mutations in the alphaglobin gene have been. An individual with one abnormal alpha globin gene is said to be a silent carrier of alpha thalassemia. Thalassemia is due to a deficit or absent production of. While the excess beta globin chains are capable of forming soluble homotetramers beta4, hbh, they are. Beta thalassemia patients with coinheritance of alpha thalassemia have a milder clinical course due to a less severe alpha beta chain imbalance. Affected individuals also have a shortage of red blood cells anemia, which can cause pale skin. Thalassemia can cause low levels of red blood cells anemia. Thalassemia in arab populations alpha and beta thalassemia are endemic in almost all arab countries probably due to the historical presence of malaria in the region and the high level of consanguinity. Alpha thalassemia is caused by a decrease in the number of alpha globin chains being produced. Large deletions, point mutations, small insertiondeletion. Beta globin is made by two genes, one on each chromosome 11.
Pallor, irritability, growth retardation, abdominal swelling, and jaundice appear during the sec. It causes the body to make less hemoglobin than normal. Thalassemia major, variably referred to as cooleys anemia and mediterranean anemia, thalassemia intermedia and thalassemia minor also called beta thalassemia carrier, beta thalassemia trait or heterozygous beta thalassemia. 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. Sickle cell anemia can be identified by hemoglobin electrophoresis alone, while both alpha and beta thalassemia need to be confirmed through molecular. Beta thalassemia trait and beta thalassemia disease. 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. Alpha thalassemia trait a person with two working copies of the alpha globin gene has alpha thalassemia trait. Hemoglobin is the part of red blood cells rbcs that carries oxygen throughout the body. Hemoglobinopathy investigations genetic testing for beta or alpha globin genes 5 thalassemia disease is subcategorized into tdt and ntdt 6 management for tdt patients requires lifelong transfusions and iron chelation to prevent severe consequences of iron overload.
An 8monthold ethnic gypsy male infant with failure to thrive from birth, mild jaundice and splenomegaly. Alpha thalassemia alpha thalassemia is the result of changes in the genes. In homozygous pthalassemia, the highly unstable achains precipitate to form inclusions, found most abundantly in the bone marrow and in the peripheral blood. This condition, in which one of the four alpha globin genes is missing or. Thalassemias are a heterogeneous grouping of genetic disorders that result from a decreased synthesis of alpha or beta chains of hemoglobin. The abnormal hemoglobin can lead to anemia not enough rbcs in the body and other medical problems. People who have this condition can pass the disease on to their children. There are at least four forms of alpha thalassemia. The term thalassemia is derived from the greek, thalassa sea and haima blood. There are at least 4 different and distinct alphathalassemias.
Treatment of beta thalassemia may include medicines and regular blood transfusions. People who have this condition can pass the disease on. Hemoglobin is the ironcontaining protein in red blood cells that carries oxygen to cells throughout the body. A person who has thalassemia trait may not have any symptoms at all or may have only mild anemia, while a person with thalassemia. Thalassemia is one of the most common inherited autosomal recessive disorders around the world. Beta thalassemia is a blood disorder that reduces the production of hemoglobin. The symptoms of thalassemia major generally appear before a childs second birthday. The presence of sickle cell trait with betathalassemia is a major hemoglobinopathy and results in manifestations of sickle cell. Difference between alpha and beta thalassemia compare the.
Beta thalassemia results from decreased production of betapolypeptide chains. Hemoglobin is a protein that carries oxygen to the body. It is a genetic trait passed down from parents to children. Beta thalassemia is an inherited blood disorder in which the body doesnt make hemoglobin normally. In alpha thalassemia, the amount of alpha chains is decreased, and in betathalassemia, the number of beta chains is decreased. The most critical step of ngs is the experimental design of the probe set to be used for dna capture. Thalassemia refers to a group of autosomal recessive disorders of haemoglobin manufacturing. This indicates that the baby has alpha thalassemia trait. The severity of alpha and beta thalassemia depends on how many of the four genes for alpha globin or two genes for beta globin are missing. If your baby has been identified with hemoglobin barts at birth, this means heshe is probably a health carrier.
Beta thalassemia results from decreased production of beta polypeptide chains. Adult hemoglobin hemoglobin a is made of alpha and beta globins. 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. In alpha thalassemia there is a reduction in the number of alpha chains. There are at least 4 different and distinct alpha thalassemias. It is important for people with thalassemia to learn how to stay healthy.
Individuals with beta thalassemia trait or beta thalassemia minor are heterozygous for beta thalassemia, or simply a carrier of beta thalassemia. Like the silent carrier, alpha thalassemia trait is not a disease and does not affect your health. When the words trait, minor, intermedia, or major are used, these words describe how severe the thalassemia is. Beta thalassemia major causes hemolytic anemia, poor. Persons with beta thalassemia major are diagnosed during infancy. But the homozygous state with both genes for alpha thalassemia is lethal before birth because no alpha chains can be made and without alpha chains there can be no hb f or hb a and without them there can be no life. Individuals who have one or two abnormal alpha globin genes have alpha thalassemia trait. Therefore, hba 2 determination should always be performed for betathalassemia carrier identification. Nov 22, 2019 in thalassemia, the production of either the alpha or beta chains are reduced, resulting in either alpha thalassemia or beta thalassemia. Diagnosis is typically by blood tests including a complete blood count, special hemoglobin tests, and genetic tests. The alpha and beta refer to which haemoglobin gene is affected, and which of the haemoglobin chains is faulty.
This condition causes mild to severe anemia, based on the type of alpha thalassemia that is inherited. Thalassemia thaluhseemeuh is a problem with red blood cells that is passed down from parents to children genetic. 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. Betathalassemia prevalence, pathophysiology and inheritance. Thalassemia genetic and rare diseases information center. Different people will have different symptoms, based on which type of beta thalassemia is inherited.
The main types of thalassaemia are called alpha thalassaemia and beta thalassaemia. 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. Normal hemoglobin consists of two alpha chains and two beta chains. An alpha thalassemia trait that can cause mild anemia. Hb h disease, which causes mild to moderately severe anemia, and an enlarged spleen the organ that removes abnormal red blood cells from circulation alpha thalassemia major is the most severe type.
In beta thalassemia, the gene for making beta globin chains doesnt work normally. The condition is called alpha thalassemia or beta thalassemia, depending on the specific genes that are missing or changed thalassemia can cause low. Laboratory diagnosis of hemoglobinopathies and thalassemia. Thalassemia in arab populations alpha and betathalassemia are endemic in almost all arab countries probably due to the historical presence of malaria in the region and the high level of consanguinity. This is the main difference between alpha and beta thalassemia. Alphathalassaemia symptoms, diagnosis and treatment. May 16, 2016 the most critical step of ngs is the experimental design of the probe set to be used for dna capture. 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 two classes. Affected individuals also have a shortage of red blood cells. Alphathalassaemia is inherited as an autosomal recessive disorder characterised by a microcytic hypochromic anaemia, and a clinical phenotype varying from almost asymptomatic to a lethal. This causes a shortage of red blood cells and low levels of oxygen in the bloodstream, leading to a variety of health problems.
Thha allasssseemmiiaa gttrraaiitt wwhhyy geett tteesstteedd. Most cases of hemoglobin variants and alpha thalassemia are detected on. Combination of a triple alphaglobin gene with beta. A person who has thalassemia trait may not have any symptoms at all or may have only mild anemia, while a person with thalassemia major may have severe symptoms and may need. Thalassemias are a group of inherited blood conditions which result in the impaired production of hemoglobin, the molecule that carries oxygen in the blood.
Thalassemia is due to decreased production of at least one globin polypeptide chain beta, alpha, gamma, delta which results in unbalanced hemoglobin synthesis. Apr 30, 2020 thalassemias are inherited blood disorders. If you have one, your body makes fewer healthy red blood cells and less hemoglobin. Each type of thalassaemia alpha and beta is then classified into more types, according to how severe the condition is. Thalassemia major is the most severe form of beta thalassemia.
Normally, people have 4 genes for alpha globin with 2 genes on each chromosome. The condition is called alpha thalassemia or beta thalassemia, depending on the specific genes that are missing or changed. Betathalassemia patients with coinheritance of alpha thalassemia have a milder clinical course due to a less severe alphabeta chain imbalance. 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.
Silent carriers of alpha thalassemia and persons with alpha or beta thalassemia trait are asymp tomatic and require no treatment. Molecular genetics of the thalassemia syndromes uptodate. Alpha thalassemia trait is an inherited abnormality of hemoglobin that results in a very mild anemia low blood hemoglobin level and smaller size of the red blood cells. Depending on the type of beta thalassemia, symptoms. The more mutated genes, the more severe your thalassemia. Thalassemia thalassemia is an inherited blood disorder in which the body produces an abnormal form of hemoglobin which results in excessive destruction of red blood cells and further leads to anemia. Thalassemia can be categorized broadly into two main categories as alpha thalassemia and beta thalassemia.
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