Misdiagnosis of β-Thalassemia Major Due to Chinese Gγ+(Aγδβ)0-Thalassemia Combined with β0-Thalassemia

delta beta-thalassemia is a rare type of thalassemia characterized by increased Hb F levels, including mainly Chinese (G)gamma((A)gamma delta beta)(0)-thalassemia, Yunnanese (G)gamma((A)gamma delta beta)(0)-thalassemia, Cantonese (G)gamma((A)gamma delta beta)(0)-thalassemia in China. Due to the low rate of delta beta-thalassemia carriers, there are few reports of delta beta-thalassemia combined with beta-thalassemia causing beta-thalassemia major. Herein, we described the combination of Chinese (G)gamma((A)gamma delta beta)(0)-thalassemia and beta-thalassemia leading to beta-thalassemia major in a Chinese patient. Hemoglobin analysis was performed by capillary electrophoresis (CE). Routine genetic analysis was carried out by gap-polymerase chain reaction (Gap-PCR) and PCR and reverse dot blot (PCR-RDB). Multiple ligation-dependent probe amplification (MLPA) was used to detect the large deletion, and Gap-PCR confirmed the deletion. A CE result showed an elevated Hb F level of 98.7% and 11.7% in the proband and her mother, but the proband was diagnosed with beta(CD17M)/beta(CD17M) using routine genetic analysis. However, her father was heterozygous for CD17 in beta-globin, and her mother was detected as SEA heterozygous. The further analysis presented that the proband had actually missed the diagnosis of Chinese (G)gamma((A)gamma delta beta)(0)-thalassemia by MLPA and PCR-RDB. Finally, the genotype of the proband was corrected from beta(CD17M)/beta(CD17M) to beta(CD17M)/beta(G gamma(A gamma delta beta)0). This is the first report of Chinese (G)gamma((A)gamma delta beta)(0)-thalassemia combined with beta-thalassemia resulting in beta-thalassemia major in China. Screening for delta beta-thalassemia by Hb analysis could be an effective method.