Hemoglobin sickle-beta thalassemia
Other Names for this Disease
- Hb S beta-thalassemia
- Sickle beta thalassemia
When no beta globin is produced by the HBB gene (called sickle cell-beta zero thalassemia), the condition is almost identical to sickle cell disease. These patients may have irreversibly sickled red blood cells, severe anemia, and frequent sickle cell crisis. When some beta globin is produced by the HBB gene (called sickle cell-beta plus thalassemia), the condition is less severe.
The Human Phenotype Ontology provides the following list of signs and symptoms for Hemoglobin sickle-beta thalassemia. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms.
The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature.
The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined.
Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
- Beta Thalassemia. Cooley's Anemia Foundation. http://www.cooleysanemia.org/updates/pdf/Beta_Thalassemia.pdf. Accessed 4/14/2011.
- Bender MA & Hobbs W. Sickle Cell Disease. GeneReviews. May 17, 2012; http://www.ncbi.nlm.nih.gov/books/NBK1377/. Accessed 12/20/2012.