Thalassemia Phenotypes and Genotypes in Taiwan: A Retrospective Study Based on Thalassemia Screening of Young Men for Military Conscription

Abstract

Prenatal thalassemia studies from Taiwan show that one-third of fetuses with genetic abnormalities have β-thalassemia major (β-TM). However, the phenotypes and genotypes of adult thalassemia warrant further investigation. From September 2006 to April 2014, 741 male candidates drafted for military service with mean corpuscular volume (MCV) <80 fL and serum ferritin >20 µg/L were analyzed. The results showed that the detection rates of α- and β-thalassemia (α- an β-thal) were 50.20% (372/741) and 49.12% (364/741), respectively. Only five patients (0.67%) were diagnosed with both α- and β-thal. The – –^SEA/αα mutation was found in 76.88% (286/372) of α-thal patients. Heterozygous mutations in IVS-II-654 (C > T) and codons 41/42 (–TCTT) accounted for 55.77% (203/364) of β-thal cases. The leukocyte counts for α- and β-thal were 6241.74 ± 1552.99 and 6622.87 ± 1814.41 × 10⁹/L, respectively (p = 0.007). The α-thal patients had lower red blood cell (RBC) mass (5.85 ± 0.44 × 10¹²/L vs. 6.09 ± 0.45 × 10¹²/L; p < 0.001) and higher hemoglobin (Hb) (12.82 ± 0.72 vs. 12.35 ± 0.71 g/dL; p < 0.001) than β-thal patients. Mean serum ferritin values were 169.67 and 241.36 µg/L, respectively, in α- and β-thal patients (p < 0.001), indicating more profound ineffective erythropoiesis in β-thal. Only four of the 741 patients underwent further hematological follow-up. Our study suggests that iron overload might be a potential problem in β-thal patients; therefore, regular follow-up is highly recommended.

• Hemoglobin (Hb)
• mutation
• Taiwan
• thalassemia

Acknowledgements

We thank Professor Shih-Lan Hsu (Department of Medical Research and Education, Taichung Veterans General Hospital, Taichung City, Taiwan) who provided consultation for the study design and manuscript writing. We also thank Mr. Tien-Hsiang Wang (Division of Hamatology/Medical Oncology, Taichung Veterans General Hospital, Taichung City, Taiwan) for technical support.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Supplementary material available online Supplementary Table 1 and 2