Question: What is (are) Alpha-thalassemia ?
Answer: Alpha-thalassemia is a blood disorder that reduces the body's production of hemoglobin. Affected people have anemia, which can cause pale skin, weakness, fatigue, and more serious complications. Two types of alpha-thalassemia can cause health problems: the more severe type is known as Hb Bart syndrome; the milder form is called HbH disease. Hb Bart syndrome may be characterized by hydrops fetalis; severe anemia; hepatosplenomegaly; heart defects; and abnormalities of the urinary system or genitalia. Most babies with this condition are stillborn or die soon after birth. HbH disease may cause mild to moderate anemia; hepatosplenomegaly; jaundice; or bone changes. Alpha-thalassemia typically results from deletions involving the HBA1 and HBA2 genes. The inheritance is complex, and can be read about here. No treatment is effective for Hb Bart syndrome. For HbH disease, occasional red blood cell transfusions may be needed.
Source: GARD

Question: What are the symptoms of Alpha-thalassemia ?
Answer: What are the signs and symptoms of Alpha-thalassemia? The Human Phenotype Ontology provides the following list of signs and symptoms for Alpha-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. Signs and Symptoms Approximate number of patients (when available) Abnormality of the heme biosynthetic pathway 90% Abnormality of immune system physiology 7.5% Biliary tract abnormality 7.5% Cognitive impairment 7.5% Hemolytic anemia 7.5% Hydrops fetalis 7.5% Hypersplenism 7.5% Myelodysplasia 7.5% Splenomegaly 7.5% Hypochromic microcytic anemia - Reduced alpha/beta synthesis ratio - 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.
Source: GARD