α⁰-Thalassemia Caused by a Novel α-Globin Gene Cluster Deletion (-^LB) Found in a Chinese Family

We report a novel large α-globin gene cluster deletion in a Chinese family from the Guangxi Zhuang Autonomous Regionfor the first time. The proband was a 20-year-old male who presented with microcytic hypochromatosis. Routine genetic analysis showed none of the common mutations in theα-globin and β-globin genes. Multiplex ligation-dependent probe amplification (MLPA) of the α-globin chain revealed there was a large deletion, which removed the entire HBA2 and HBA1 genes, HBQ gene, HBZ gene, and major regulatory element HS-40, eliminating more than 134 kb from the α-globin chain. Subsequently, pedigree analysis revealed that the proband inherited the novel deletion from his father. By consultation of literature and databases, it was confirmed as a hitherto undescribed chain deletion and named Laibin deletion (-^LB) for the origin of the proband.