Abstract
Objective: To characterize the phenotypic and hematological features of β-thalassemia carriers with concomitant α-globin gene triplication. Methods: A retrospective case series was conducted on three pediatric patients diagnosed with β-thalassemia carrier status combined with α-globin gene triplication at our hospital between January 2018 and December 2022. Detailed clinical data, including medical history, physical examination findings, hematological parameters, genetic test results, and follow-up records, were collected and comprehensively analyzed. Genetic testing was performed using Next-Generation Sequencing (NGS) based on combinatorial probe-anchor polymerization sequencing (cPAS) technology for both α-globin gene triplication and β-globin gene mutations. Results: Case 1: A 5-year-and-9-month-old female with β⁺-thalassemia combined with αααanti3.7, presenting with pallor and mild microcytic hypochromic anemia (hemoglobin (HGB): 102 g/L). Case 2: A 2-year-and-7-month-old male with β⁺-thalassemia combined with αααanti4.2 was asymptomatic with only reduced mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH). Case 3: A 10-year-old male with β⁺-thalassemia combined with αααanti4.2, presenting with mild pallor, growth retardation, mild anemia indicated by HGB, and slightly enlarged spleen on ultrasound. All three cases were diagnosed with mild microcytic hypochromic anemia. No significant decline in hematological parameters was observed with increasing age after 6 months of age. Concurrent infections led to transient deterioration of anemia (progressing to moderate anemia), which resolved following infection control. Conclusion: Co-inheritance of α-globin gene triplication in β-thalassemia carriers may be associated with non-transfusion-dependent phenotypes, exhibiting mild and heterogeneous clinical manifestations. This underscores the importance of comprehensive prenatal diagnostic counseling.