First Reported Case of Hemoglobin H Disease Caused by the Rare α-Globin Gene Mutation (HBA2 c.244delT) in a Chinese Family.

Microcytosis of red cells and mild anemia are common in thalassemia carriers but those phenotypes are not specific. It is really a challenge for clinical interpretation of those variants. Co-segregation with disease in affected family members or specific phenotypes such as the abnormal Hb H are very helpful to assess the pathogenicity of rare variants. HBA2 c.244delT was only reported in a 19-year-old woman with mild microcytosis and hypochromia. There was no other information about this variant reported before. We first described the case of this variant compounded with SEA deletion who presented with moderate anemia. Co-segregation analysis was confirmed by Sanger sequencing. Our study gave evidence for predicting the pathogenicity of this rare missense variant.