A Woman with Missing Hb A(2) Due to a Novel (epsilon gamma)delta beta(0)-Thalassemia and a Novel delta-Globin Variant Hb A(2)-Gebenstorf (HBD: c.209G > A)

A woman completely lacking Hb A(2)on the high performance liquid chromatography (HPLC) analysis, presented with a novel deletional (epsilon gamma)delta beta(0)-thal and a delta-globin gene variant. This combination causes a beta-thalassemia (beta-thal) minor phenotype. The woman was referred by a hematologist due to abnormal blood counts. Multiplex ligation-dependent probe amplification (MLPA) and microarray analysis showed a heterozygous, 177 kb long deletion that removed the locus control region enhancer plus the epsilon,(G)gamma and(A)gamma genes. Additional sequencing revealed a novel variantHBD: c.209G>A, p.Gly70Asp in the heterozygous state, called Hb A(2)-Gebenstorf. The combination of the two variants explains the lack of Hb A(2)in this woman.