A Novel 223 kb Deletion in the Beta-globin Gene Cluster Was Identified in a Chinese Thalassemia Major Patient

Introduction: Although mutations in the human beta-globin gene cluster are essentially point mutations, several large deletions have been described in recent years.

Methods: We have identified a novel 223 kb deletion in a Chinese patient by multiplex ligation-dependent probe amplification and characterized it by next-generation sequencing, Gap-PCR, and DNA sequence analysis.

Results: The deletion extends from the 3'UTR of the δ globin gene (HBD) to 215 kb downstream of the HBB. Compound heterozygous with the typical β-thalassemia-CD41-42(-CTTT) mutation, the proband presented with microcytosis and hypochromic red cells, and required regulate transfusion. The patient was clinically diagnosed with thalassemia major.

Conclusion: Our study widens the mutation spectrum of β-thalassemia. In addition, this case may spark future studies of the regulatory regions of the beta-globin gene cluster.