Thalassemia results from variants in the HBA1 and HBA2 genes, both of which provide instructions for making alpha-globin, a critical component of normal hemoglobin. When one or both of these genes carry pathogenic variants, the alpha-globin chains needed for hemoglobin assembly are produced in insufficient quantities, disrupting the balance of hemoglobin components and impairing red blood cell function. Individuals inherit two copies of each globin gene, and the number of affected gene copies largely determines the severity of the condition. Because this condition requires inheriting altered copies from each parent in its more significant forms, it may be more common in families where parents share common ancestors, as this increases the likelihood that both parents carry the same rare genetic variant. Genetic counseling is recommended for affected individuals and their families.

Diagnosis is confirmed through molecular genetic testing identifying pathogenic variants in HBA1 and HBA2. A complete blood count typically reveals low hemoglobin levels and characteristic changes in red blood cell size and shape, providing an important early clinical clue. Hemoglobin electrophoresis or high-performance liquid chromatography can identify abnormal hemoglobin patterns and help quantify the specific hemoglobin fractions present. Because many features of thalassemia can overlap with other inherited anemias and hemoglobin disorders, molecular genetic testing is essential to confirm the diagnosis and distinguish it from conditions with similar clinical presentations. Family history and carrier testing of parents can also provide important diagnostic and counseling information.

Management of thalassemia is tailored to the severity of the individual's condition and typically involves a multidisciplinary care team. Supportive measures such as regular blood transfusions are central to care for individuals with significant anemia, helping to maintain adequate hemoglobin levels and support normal development. Iron chelation therapy is an important component of ongoing management for those receiving regular transfusions, as excess iron accumulation can damage the heart, liver, and other organs over time. Mitapivat (PYRUKYND) is an FDA-approved treatment available for eligible individuals with thalassemia. Additional therapies are under investigation and in clinical development, including etavopivat and other agents with orphan drug designation. Regular surveillance of organ function, including cardiac and liver monitoring, is an essential part of long-term care. Patients should discuss treatment options with their healthcare team to determine which therapies may be appropriate for their specific situation.

The course of thalassemia is highly variable and depends significantly on the number of affected gene copies, the severity of hemoglobin deficiency, age at diagnosis, and access to specialized care. With current standards of care, many individuals with thalassemia are able to lead active and meaningful lives, particularly when diagnosis is made early and consistent treatment is maintained. Regular transfusion programs and advances in iron chelation therapy have substantially improved long-term outcomes for those with more significant forms of the condition. Outcomes vary depending on symptom severity, the presence of complications such as iron overload or organ damage, and adherence to monitoring and treatment. Ongoing follow-up with a hematologist experienced in hemoglobin disorders is important for optimizing long-term health.

Thalassemia is an active area of research, with numerous ongoing clinical trials investigating new treatment approaches. Research efforts are exploring a range of strategies including novel small molecules, gene-based therapies, and other agents aimed at improving hemoglobin production or reducing disease burden. Several therapies are in various stages of clinical development and have received orphan drug designation, reflecting the significant unmet need in this patient community. Individuals interested in participating in clinical trials can search ClinicalTrials.gov or consult their care team about eligibility and available options.