Thalassemia is a hereditary hemolytic anemia with a severity ranging from mild, non-transfusion dependent to severe chronic anemia requiring lifelong transfusion. Transfusional iron overload is a major complication in patients with transfusion-dependent thalassemia (TDT). Telomeres are sequences of nucleotides forming the end caps of chromosomes that act as a DNA repair system. Iron overload in thalassemia can cause increased oxidative stress which leads to cellular damage and senescence. This may result in telomere length shortening. The degree of telomere length shortening may reflect the severity of thalassemia. This research aimed to study the leukocyte telomere length in patients with TDT in comparison to non-thalassemic individuals and to identify the clinical and laboratory parameters that are associated with telomere length. We conducted a cross-sectional study in patients with TDT aged ≥18 years. Leukocyte telomere length was measured by real-time quantitative PCR. Sixty-five patients with TDT were enrolled onto the study. There were 37 female patients (54.4%). The median age was 27 (18–57) years, and mean pre-transfusion hemoglobin level was 7.1 (± 1.07) g/dL. The mean telomere to single copy gene (T/S) ratios of patients with TDT and the controls were 0.72 ± 0.18 and 0.99 ± 0.25, respectively (p < 0.0001). There was a significant correlation between the T/S ratio and age (p = 0.0002), and hemoglobin level (p = 0.044). There was no correlation between telomere length and other factors. Our study showed that TDT patients had shorter leukocyte telomere length compared with controls. Leukocyte telomere shortening in TDT was an aging-dependent process and associated with lower hemoglobin level.

中文翻译：

---

输血依赖型地中海贫血患者的白细胞端粒长度。

地中海贫血是一种遗传性溶血性贫血，严重程度从轻度，非输血到严重的慢性贫血，需要终身输血。输血铁性超负荷是输血依赖型地中海贫血（TDT）患者的主要并发症。端粒是形成染色体末端的核苷酸序列，可作为DNA修复系统。地中海贫血中的铁超载会导致氧化应激增加，从而导致细胞损伤和衰老。这可能导致端粒长度缩短。端粒长度缩短的程度可能反映了地中海贫血的严重程度。这项研究旨在研究TDT患者与非地中海贫血患者相比的白细胞端粒长度，并确定与端粒长度相关的临床和实验室参数。我们对年龄≥18岁的TDT患者进行了横断面研究。通过实时定量PCR测量白细胞端粒长度。65名TDT患者被纳入研究。有37名女性患者（54.4％）。中位年龄为27（18-57）岁，平均输血前血红蛋白水平为7.1（±1.07）g / dL。TDT患者和对照组的端粒与单拷贝基因（T / S）的平均比分别为0.72±0.18和0.99±0.25（p <0.0001）。T / S比与年龄（p = 0.0002）和血红蛋白水平（p = 0.044）之间存在显着相关性。端粒长度与其他因素之间没有相关性。我们的研究表明，与对照组相比，TDT患者的白细胞端粒长度较短。