If there are three defective alpha genes, there's moderate disease, called hemoglobin H, or HbH, disease.
如果有3个α基因异常，则出现中度地中海贫血，即血红蛋白H病（HbH病）。
英语百科
Alpha-thalassemia
（重定向自Hemoglobin H）
Alpha-thalassemia (α-thalassemia, α-thalassaemia) is a form of thalassemia involving the genes HBA1 and HBA2. Alpha-thalassemia is due to impaired production of alpha chains from 1,2,3, or all 4 of the alpha globin genes, leading to a relative excess of beta globin chains. The degree of impairment is based on which clinical phenotype is present (how many genes are affected).