balanced franslocation平衡易位16Barts hydrops fetalis Barts水肿胎， Barts胎尔水肿综合征64basal cell nevus syndrome基底细胞痣118Becker′s muscular dystrophy轻型假肥大型肌营养不良71β-globin gene clusteβ珠蛋白因簇60β-thalassemiaβ地中海贫血65Bloom′s syndrome Bloom′s综合征19，119blunt terminus平整末端157brachydactyly短指症49，86break point cluster region断点簇区122breakage断裂14brnachitis,chronic慢性支气管炎115bronchial asthma支气管哮喘115Burkitt lymphoma非洲恶性淋巴瘤122