National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Beta-thalassemia


Other Names:
Beta thalassemia major; Cooley's anemia; Beta thalassemia intermedia; Beta thalassemia major; Cooley's anemia; Beta thalassemia intermedia; Beta thalassemia minor; Erythroblastic anemia; Mediterranean anemia; Thalassemia, Hispanic gamma-delta-beta ; Thalassemias, beta- See More
Categories:
This disease is grouped under:
Beta-thalassemia is a blood disorder that reduces the body's production of hemoglobin. Low levels of hemoglobin lead to a shortage of mature red blood cells and a lack of oxygen in the body. People with beta-thalassemia have anemia, which can cause paleness, weakness, fatigue, and more serious complications.[1] There are two main forms of beta-thalassemia, classified based on the severity of symptoms:[2]
  • Thalassemia major (also called Cooley's anemia) - the more severe form, causing severe anemia and enlarged liver and spleen (hepatosplenomegaly). This form usually becomes apparent before 2 years of age. If not treated, it causes failure to thrive and a shortened life expectancy. Treatment involves regular transfusions and chelation therapy to reduce iron overload. Treatment allows for normal growth and development. Bone marrow transplantation or cord blood transplantation may eliminate the need for regular treatment. 
  • Thalassemia intermedia - the less severe form, becoming apparent later and causing milder anemia that does not require regular blood transfusions. People with this form are also at risk for iron overload.
Beta-thalassemia is caused by mutations in the HBB gene and is typically inherited in an autosomal recessive manner. This means that people with thalassemia major or thalassemia intermedia have a mutation in both of their copies of the HBB gene.

People who have only one HBB gene mutation (carriers) typically are said to have thalassemia minor (or trait) and usually do not have symptoms, but may have some symptoms of anemia.[1][2][3] In some cases, anemia is worsened if there is a nutritional deficiency such as with iron, folic acid or vitamin B12.[4]

Very rarely, the inheritance of beta-thalassemia may be dominant. In this case, a person has only one mutated HBB gene, but has signs and symptoms of beta-thalassemia major or beta-thalassemia intermedia.[5]

The exact treatment plan for beta-thalassemia depends on the symptoms and severity in each person.[2]

Last updated: 6/18/2018

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 21 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormal hemoglobin 0011902
Microcytic anemia 0001935
Pallor 0000980
Splenomegaly
Increased spleen size
0001744
30%-79% of people have these symptoms
Abnormal skull morphology
Abnormality of the skull
0000929
Abnormality of iron homeostasis 0011031
Abnormality of temperature regulation
Poor temperature regulation
0004370
Hepatomegaly
Enlarged liver
0002240
Hypogonadotropic hypogonadism 0000044
Irritability
Irritable
0000737
Muscle weakness
Muscular weakness
0001324
Reduced bone mineral density
Low solidness and mass of the bones
0004349
Respiratory insufficiency
Respiratory impairment
0002093
5%-29% of people have these symptoms
Cholelithiasis
Gallstones
0001081
Hepatitis
Liver inflammation
0012115
Hypertrophic cardiomyopathy
Enlarged and thickened heart muscle
0001639
Skin ulcer
Open skin sore
0200042
Thrombocytopenia
Low platelet count
0001873
Venous thrombosis
Blood clot in vein
0004936
Percent of people who have these symptoms is not available through HPO
Hypochromic microcytic anemia 0004840
Reduced beta/alpha synthesis ratio 0011906
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Last updated: 7/1/2020
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. The parents of a person with an autosomal recessive condition each carry one copy of the mutated gene and are referred to as carriers. When two carriers have children, each child has a 25% (1 in 4) chance to be affected, a 50% (1 in 2) chance to be a carrier like each parent, and a 25% (1 in 4) chance to be unaffected and not a carrier. Sometimes, people with only one HBB gene mutation in each cell (carriers) do have mild anemia. These people are said to have 'beta-thalassemia minor' or 'beta-thalassemia trait.'[1]

In a small percentage of families, the condition is inherited in an autosomal dominant manner. In these cases, one mutated copy of the gene in each cell is enough to cause the signs and symptoms of beta-thalassemia.[1]
Last updated: 6/18/2018

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

  • Thiotepa (Brand name: Tepadina) - Manufactured by Adienne S.A.
    FDA-approved indication: To reduce the risk of graft rejection when used in conjunction with high-dose busulfan and cyclophosphamide as a preparative regimen for allogeneichematopoietic progenitor (stem) cell transplantation (HSCT) for pediatric patients with class 3 beta-thalassemia.
    National Library of Medicine Drug Information Portal

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Beta-thalassemia. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Financial Resources

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • You can obtain information on this topic from the Centers for Disease Control and Prevention (CDC). The CDC is recognized as the lead federal agency for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States.
  • Genetics Home Reference (GHR) contains information on Beta-thalassemia. This website is maintained by the National Library of Medicine.
  • The National Center for Biotechnology Information (NCBI) was established in 1988 as a national resource for molecular biology information.  Click on the link to view information on this topic.
  • The National Heart, Lung, and Blood Institute (NHLBI) has information on this topic. NHLBI is part of the National Institutes of Health and supports research, training, and education for the prevention and treatment of heart, lung, and blood diseases.
  • The National Human Genome Research Institute's (NHGRI) website has an information page on this topic. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Beta-thalassemia. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

  • My partner and I have both been diagnosed with beta-thalassemia minor. What is the likelihood of having a child without beta-thalassemia? See answer

  • I've been told that I am a carrier for beta-thalassemia and I have low levels of hemoglobin. Can I donate blood? See answer


  1. Beta thalassemia. Genetics Home Reference. September, 2015; http://ghr.nlm.nih.gov/condition/beta-thalassemia.
  2. Origa R. Beta-Thalassemia. GeneReviews. January 25, 2018; http://www.ncbi.nlm.nih.gov/books/NBK1426/.
  3. Benz EJ. Clinical manifestations and diagnosis of the thalassemias. UpToDate. Waltham, MA: UpToDate; January 8, 2018;
  4. Choudhry VP. Thalassemia Minor and Major: Current Management. The Indian Journal of Pediatrics. August, 2017; 84(8):607-611. https://www.ncbi.nlm.nih.gov/pubmed/28435994.
  5. Khera R, Singh T. Dominant ß-thalassemia - A rare entity!. Indian J Pathol Microbiol. 2012; 55(3):422-423. http://www.ijpmonline.org/article.asp?issn=0377-4929;year=2012;volume=55;issue=3;spage=422;epage=423;aulast=Khera.