Diagnosis is typically by blood tests including a complete blood count, special hemoglobin tests, and genetic tests. Three clinical and hematological conditions of increasing severity are recognized. Carrying alpha zero thalassaemia a carrier can use this booklet to help explain carrying alpha zero thalassaemia to their partner, blood relatives and others. 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. Human hemoglobin is a tetrameric protein consisting of two alpha. Get all of these illustration organized by subject in pdf form at s. The following are pdf formatted files in various languages. Jul 29, 2015 alpha thalassemia is a blood disorder that reduces the bodys production of hemoglobin. Guidelines for investigation of the alpha and beta thalassaemia traits.
A total of 6946 subjects were enrolled for evaluating alphabeta thalassemia from 2012 to 2018. 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. The thalassemias are an inherited group of disorders in which mutations in genes expressing alpha globin or beta globin result in impaired hemoglobin synthesis and microcytic anemia of varying severity. Beta thalassemia trait and beta thalassemia disease. Coinheritance of alpha thalassemia 1 and hemoglobin e beta zero thalassemia. Physicians often mistake alpha thalassemia trait for iron deficiency anemia and incorrectly prescribe iron supplements that have no effect on the anemia. Like the silent carrier, alpha thalassemia trait is not a disease and does not affect your health. Betathalassemia antonio cao, md1, and renzo galanello, md2.
Our primary goal is to help improve the quality of life for all patients with this terrible disease. Phenotypic effect of heterozygous alpha and beta 0. 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. Full text full text is available as a scanned copy of the original print version. Scribd is the worlds largest social reading and publishing site. The alpha chain is involved in alpha thalassemia and the beta chain is affected in the more familiar beta thalassemia. Beta thalassemia mechanism of disease beta thalassemia is a rare, inherited blood disorder characterized by low levels of hemoglobin, which resides in red blood cells and carries oxygen throughout the body. On the other hand, deletion of three genes results in significant production of hemoglobin h consisting of four beta chain. Thalassemias slide 1 by the end of the lecture, the. What does it mean to be a carrier of alpha plus thalassemia. Depending on family history, if a persons parents or grandparents had beta thalassemia major or intermedia, there is a 75% 3 out of 4 probability see inheritance chart at top of page of the mutated gene being inherited by an offspring. Apr 03, 2018 thalassaemia major genetics of thalassemia adult hemoglobin composed two alpha and two beta chains. There are two main types, alpha thalassemia and beta thalassemia.
It is normal for people whose ancestors come from these areas to carry mild alpha thalassaemia, so you should not worry about it. Beta thalassemia can combine with other altered beta genes and cause problems also. Symptoms appear in the first two years of life and include paleness of the skin, poor appetite, irritability, and failure to grow. Alpha thalassemia nord national organization for rare. In undiagnosed cases screened for beta thalassemia major, we found mediterranean. Since reticulocytes manufacture equimolecular quantities of alpha and beta chains. Disorders of beta globin, such as sickle cell disease and beta thalassemia major, are not clinically apparent until several months of age, when the switch from hemoglobin f to hemoglobin a synthesis. Automated measurement of red blood cell microcytosis and hypochromia in iron deficiency and beta thalassemia. The fact that you are a beta thalassaemia carrier means other members of your family could be carriers too.
As illustrated, the couple has one chance in four that a child will inherit two thalassemia genes. Hemoglobin, which carries oxygen to all cells in the body, is made of two different parts, called alpha and beta. For example, if one parent has beta thalassemia trait and the other parent has sickle cell trait another type of altered beta globin gene, there is a 25% chance of having a child with sickle beta thalassemia. Carrying alpha zero thalassaemia thalassemia club of thailand. 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. This causes a shortage of red blood cells and low levels of oxygen in the bloodstream, leading to a variety of health problems.
Affected people have anemia, which can cause pale skin, weakness, fatigue, and more serious complications. In general, this results in an excess of alpha globins that form insoluble tetrameric inclusions in the red blood cell. Alpha thalassemia is one of the most common hemoglobin genetic abnormalities and is caused by the reduced or absent production of the alpha globin chains. Anemia is caused by a lower than normal number of red blood cells or not enough hemoglobin in the red blood cells. Diagnosis of beta thalassemia can be done by fetal dna analysis for. How i treat thalassemia blood american society of hematology.
Thalassemia is due to a deficit or absent production of. Thalassaemia minor can refer to people with either alpha or beta thalassaemia. For example, a person with beta thalassaemia minor has one changed copy of the hbb gene, and one unchanged copy of the gene. Because they have one functioning copy of the gene, their health is not affected by beta thalassaemia.
In beta thalassemia, the gene for making beta globin chains doesnt work normally. Depending on family history, if a persons parents or grandparents had beta thalassemia major or intermedia, there is a 75%. Alpha thalassemia normal production of alpha chains is absent which results in excess production of gamma globin chains in the fetus and newborn or beta globin chains in children and adults. Thalassemias national library of medicine pubmed health. Alpha thalassemia minor and beta thalassemia minor, also known as alpha thalassemia trait or beta thalassemia trait, are common conditions in many demographics. Alpha thalassemia deletions found in suspected cases of beta. 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. Beta thalassemia is an inherited disease characterized by mild to severe anemia, poor growth, enlargement of the spleen, and skeletal changes. Along with patient care, medical research is a primary focus at the comprehensive thalassemia center at ucsf benioff childrens hospital oakland. Get a printable copy pdf file of the complete article 1.
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. 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. While the excess beta globin chains are capable of forming soluble homotetramers beta. Jun 18, 2018 beta thalassemia major and beta thalassemia intermedia are usually inherited in an autosomal recessive manner, which means both copies of the hbb gene in each cell have mutations. Alpha mutations, genetic heterogeneity, globin genes, hemoglobin disorders, somatic deletion, splenomegaly. Silent carriers of alpha thalassemia and persons with alpha or beta thalassemia trait are asymp tomatic and require no treatment. Individuals with thalassemia major usually present within the first two years of life.
In contrast, gamma globin mutations are evident in the neonate and then disappear as gamma globin synthesis wanes. A total of 6946 subjects were enrolled for evaluating alpha beta thalassemia from 2012 to 2018. Evaluation of alpha hemoglobin stabilizing protein ahsp as. Those that result in the functional depletion of both pair of. May 01, 2004 krishnamurti l, chui dh, dallaire m, leroy b, waye js, perentesis jp. Grasp the cellular pathogenesis of alpha and beta thalassemias. Beta thalassemia major also called cooleys anemia is a serious illness. Is it possible to have both alpha thalassemia and beta. There are two main types of thalassemia, alpha thalassemia and beta thalassemia. If you need to, you can download the acrobat reader here. The association of the g6pd defect with this thalassemia gene complex may eventually contribute to this effect. Thalassemias slide 1 by the end of the lecture, the student. Alpha thalassemia is caused by reduced or absent production of alpha globin subunits, while beta thalassemia is caused by reduced or absent production of beta globin subunits.
Analysis of the genotype at the alpha and beta loci and testing for the presence of ameliorating genetic factors may be useful in this differentiation see later. We suggest, therefore, that screening programs for heterozygous beta thalassemia in populations where alpha thalassemia is also prevalent, should incorporate the determination of hba2 in the first set of tests. 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. Normal hemoglobin consists of two alpha chains and two beta chains. Carrier frequencies of beta thalassemia vary from 1% to 5% while prevalence data for alpha thalassemia are scant. Alphathalassemia is a blood disorder that reduces the bodys production of hemoglobin. Thalassemias are a group of inherited blood conditions which result in the impaired production of hemoglobin, the molecule that carries oxygen in the blood. To download a pdf file with information on alpha thalassemia. Family history and ancestry are factors which increase the risk of beta thalassemia.
Alpha thalassemia multiplex ligation dependent probe amplification mlpa and multiplex pcr alpha globin sequencing beta thalassemia beta globin sequencing the test examines the complete beta globin coding sequence, the splice sites and other intronic regions known to harbor mutations, the proximal promoter region. 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. 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. The two main types are called alpha and beta thalassemia, depending on. Normal hemoglobin, also called hemoglobin a, has four protein chainstwo alpha globin and two beta globin. Alpha thalassemia trait a person with two working copies of the alpha globin gene has alpha thalassemia trait. People who have thalassemias can have mild or severe anemia uhneemeuh. Jun 17, 2011 inheritance of hemoglobin genes from parents with thalassemia trait. The parents of a person with an autosomal recessive condition each carry one copy of the mutated gene and are referred to as carriers. Pdf on mar 21, 2012, vefik arica and others published alpha thalassemia disorders find, read and cite all the research you need on. Because the alpha and beta thalassemia gene mutations are common, it is possible for a baby to inherit one from mom and another from dad. Normal alpha globin genes found on chromosome 16 people who do not produce enough alpha globin protein chains have alpha thalassemia. Alpha thalassemia intermedia, or hemoglobin h disease, causes.
Clinically, both alpha and betathalassemia may occur in the major. Oct 09, 2006 since thalassemia is not a single disorder but a group of related disorders that affect the human body in similar ways, it is important to understand the differences between the various types of thalassemia. Adult hemoglobin composed two alpha and two beta chains. Carrying the gene for alpha plus thalassaemia does not cause any illness, however it. Silent carrier state the mildest form of beta thalassemia. Betathalassemia genetic and rare diseases information. The child would have a severe form of thalassemia thalassemia major or thalassemia intermedia. Beta thalassemia trait when you have one working copy of the beta globin gene and one nonworking copy you have beta thalassemia trait. 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. Describe the clinical and laboratory features of beta thalassemia minor trait and beta thalassemia major and the different types of alpha thalassemia. Alpha thalassemia usually caused by gene deletion beta thalassemia usually caused by mutation. Alpha thalassemia, beta thalassemia, and sickle cell disease, collectively called hemoglobinopathies, are blood disorders with variable presentation ranging from chronic but treatable disease to a neonatal. The two main types are called alpha and beta thalassemias, depending on which part of an oxygencarrying protein called hemoglobin is lacking in the red blood cells. Alpha thalassemia normally, alpha globin chain is made by four genes two from each parent, two on each strand of chromosome 16.
Alpha thalassemia a normal person carries a linked pair of. When thalassemia is called alpha or beta, this refers to the part of hemoglobin that isnt being made. The child could be trait in both alpha and beta, or less likely, be disease in one and trait in the other. It involves a deficiency of one of the components of hemoglobin, the oxygencarrying molecule in the blood. Disorders of beta globin, such as sickle cell disease and beta thalassemia major, are not clinically apparent until several months of age, when the switch from hemoglobin f to hemoglobin a synthesis reveals the defect. Mutated thalassemia alpha 0 thalassemia more than 20 mutations have been found. Thalassemia is an inherited blood disorder that reduces the production of functional hemoglobin the protein in red blood cells that carries oxygen. It is passed down from one or both parents through their genes. Kalpana malla md pediatrics manipal teaching hospital download more documents and. Jan 11, 2018 the alpha chain is involved in alpha thalassemia and the beta chain is affected in the more familiar beta thalassemia.
The thalassemia support foundation tsf is a nonprofit organization that was founded by patients, parents, and friends affected by thalassemia. If either the alpha or beta part is not made, there arent enough building blocks to make normal amounts of. Two types of alpha thalassemia can cause health problems. 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. Alpha and beta thalassemia american family physician. Most beta thalassemia cases result from nucleotide deletions or substitutions. Alphathalassemia genetic and rare diseases information. Your body makes less of the beta chains, but is still able to make plenty of. Alpha thalassemia trait causes the size of the red blood cells to be smaller than usual. Nathan division of hematology of the department of medicine of the childrens hospital medical center, boston, massachusetts 02115. Slide hemoglobin h disease y second most severe form alpha thalassemia. Results in microcytic, hypochromic anemias of varying severity.
There are two primary types of thalassemia disease. Thalassemia is an inherited blood disorder that is passed down through the parents genes. Alpha thalassemia alpha thalassemia is the result of changes in the genes for the alpha globin component in hemoglobin. Med deletion at specifically 875 bp on agarose gel. Thalassemia includes a number of different forms of anemia red blood cell deficiency.
To download a pdf file with information on alpha thalassemia, please click here. Carrier frequencies of beta thalassemia vary from 1% to 5% while prevalence data for alpha thalassemia. Alpha thalassemia is common in africa, asia, and the mediterranean. Thalassemia genetic and rare diseases information center. Treatment of thalassemia major includes regular rbc transfusions. Thalassemia research and care at ucsf benioff childrens hospital oakland. It is a good idea to talk to your blood relatives such as your parents, brothers, sisters, uncles. Beta thalassemia disease cooleys anemia information for physicians and other health care professionals definition beta thalassemia is an inherited red blood cell disorder that results in the complete absence or decreased synthesis of the beta. Guidelines for investigation of the alpha and beta. Alpha thalassemia disease and beta thalassemia disease. Alpha thalassemia an overview sciencedirect topics.
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