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The +33 C>G variant [NM_000518.5(HBB):c.-18C>G] in the 5' untranslated region (UTR) of the ß-globin gene is described in the literature as both mild and silent, while it causes a phenotype of thalassemia intermedia in the presence of a severe ß-thalassemia allele. Despite its potential clinical significance, the determination of its pathogenicity according to established standards requires a greater number of published cases and co-segregation evidence than what is currently available. The present study provides an extensive phenotypic characterization of +33 C>G using 26 heterozygous and 11 compound heterozygous novel cases detected in Cyprus and employs computational predictors (CADD, RegulomeDB) to better understand its impact on clinical severity. Genotype identification of globin gene variants, including α- and δ-thalassemia determinants, and rs7482144 (XmnI) was carried out using Sanger sequencing, gap-PCR, and restriction enzyme digestion methods. The heterozygous state of +33 C>G had a silent phenotype without apparent microcytosis or hypochromia, while compound heterozygosity with a ß+ or ß0 allele had a spectrum of clinical phenotypes. Awareness of the +33 C>G is required across Mediterranean populations where ß-thalassemia is frequent, particularly in Cyprus, with significant relevance in population screening and fetal diagnostic applications.

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Initiation of regular transfusion in transfusion-dependent thalassemia (TDT) is based on the assessment of clinical phenotype. Pathogenic HBB variants causing ß-thalassemia are important determinants of phenotype and could be used to aid decision making. We investigated the association of HBB genotype with survival in a cohort study in the four thalassemia centres in Cyprus. HBB genotype was classified as severe (ß0/ß0 or ß+/ß0), moderate (ß+/ß+), or mild (ß0/ß++ or ß+/ß++). Risk factors for mortality were evaluated using multivariate Cox proportional-hazards regression. 537 subjects were followed for a total of 20,963 person years. 80.4% (95% CI 76.4-84.7) of individuals survived to 50 years of age with increasing rates of liver, infection and malignancy-related deaths observed during recent follow-up. We evaluated non-modifiable risk factors and found worse outcomes associated with male sex (Hazard ratio 1.9, 95% CI 1.1-3.0, p=0.01) and milder genotype (Hazard ratio 1.6, 95% CI 1.1-2.3, p=0.02). The effect of genotype was confirmed in a second model, which included treatment effects. Patients with a milder genotype initiated transfusion significantly later and had reduced blood requirements compared to those with moderate or severe genotypes, although pre-transfusion hemoglobin levels did not differ between genotypes. Our results suggest that early treatment decisions to delay transfusion and different long-term treatment strategies in milder genotypes have led to adverse long-term effects of under-treated thalassemia and worse survival. We propose that HBB genotype determination and use of this information to aid in decision making can improve long-term outcomes of thalassaemia patients.

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We describe the identification of a novel missense mutation in the second zinc finger of KLF1 in two siblings who, based on their genotype, are predicted to suffer from beta thalassemia major but are, in fact, transfusion-free and in good health. These individuals, as well as two additional members of the same family also carrying this KLF1 mutation, exhibit high levels of fetal hemoglobin (HbF). KLF1 is an erythroid transcription factor, which plays a critical role in the regulation of the developmental switch between fetal and adult hemoglobin by regulating the expression of a multitude of genes including that of BCL11A. The mutation appears to be the main candidate responsible for the beta thalassemia-ameliorating effect as this segregates with the observed phenotype and also exogenous expression of the KLF1 mutant protein in human erythroid progenitor cells resulted in the induction of γ-globin, without, however, affecting BCL11A levels. This report adds to the weight of evidence that heterozygous KLF1 mutations can ameliorate the severity of the ß-thalassemia major phenotype.

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AIM: To examine whether hemodialysis (HD) patients with restless legs syndrome (RLS) are subjects of greater fatigue and impaired quality of life (QoL) compared to HD patients without RLS. METHODS: Eighty five stable HD patients participated in this study. According to their RLS status, the patients were divided into the RLS group (n = 23) and the non-RLS group (n = 62). QoL, fatigue, sleep quality, daily sleepiness and depression symptoms were assessed by using various questionnaires. Finally, biochemical parameters including iron, ferritin, hemoglobin, hematocrit and parathormone were assessed. RESULTS: The HD patients with RLS scored worse in all the questionnaires used in the study (P < 0.05). The patients with RLS were more likely to receive the HD therapy on the morning shift, whilst 43.5% of the RLS patients reported to experience the RLS symptoms also during HD. The severity of RLS was correlated with fatigue, depression score and sleep quality (P < 0.05). CONCLUSION: HD patients with RLS are subject to lower QoL related parameters and greater fatigue compared to HD patients without RLS. RLS should be successfully managed in order to improve the QoL of the sufferers.

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OBJECTIVES: Thalassaemia is a potentially lethal inherited anaemia, caused by reduced or absent synthesis of globin chains. Measurement of the minor adult haemoglobin Hb A2, combining α- with δ-globin, is critical for the routine diagnosis of carrier status for α- or ß-thalassaemia. Here, we aim to characterize a novel δ-globin variant, Hb A2 Episkopi, in a single family of mixed Lebanese and Cypriot ancestry with mild hypochromic anaemia and otherwise normal globin genotype, which also presents with a coincidental 0.78-Mb sequence duplication on chromosome 1 (1q44) and developmental abnormalities. METHODS: Analyses included comprehensive haematological analyses, cation-exchange high-performance liquid chromatography (CE-HPLC), cellulose acetate electrophoresis (CAE), Sanger sequencing and structure-based stability predictions for Hb A2 Episkopi. RESULTS: The GCT > GTT missense mutation, underlying Hb A2 Episkopi, HBD:c.428C > T, introduces a cd142 codon change in the mature protein, resulting in reduced normal Hb A2 amounts and a novel, less abundant Hb A2 variant (HGVS: HBD:p.A143V), detectable as a delayed peak by CE-HPLC. The latter was in line with structure-based stability predictions, which indicated that the substitution of a marginal, non-helical and non-interface residue, five amino acids from the δ-globin chain carboxy-terminus, was moderately destabilizing. DISCUSSION: Detection of the new variant depends on the diagnostic set-up and had failed by CAE and on an independent CE-HPLC system, which, in unfavourable circumstances, may lead to misdiagnoses of ß-thalassaemia as α-thalassaemia. Given the mixed background of the affected family, the ethnic origin of the mutation is unclear, and this study thus suggests awareness for possible detection of Hb A2 Episkopi in both the Cypriot and the Lebanese populations.

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Haemoglobinopathies are the most common monogenic diseases, posing a major public health challenge worldwide. Cyprus has one the highest prevalences of thalassaemia in the world and has been the first country to introduce a successful population-wide prevention programme, based on premarital screening. In this study, we report the most significant and comprehensive update on the status of haemoglobinopathies in Cyprus for at least two decades. First, we identified and analysed all known 592 ß-thalassaemia patients and 595 Hb H disease patients in Cyprus. Moreover, we report the molecular spectrum of α-, ß- and δ-globin gene mutations in the population and their geographic distribution, using a set of 13824 carriers genotyped from 1995 to 2015, and estimate relative allele frequencies in carriers of ß- and δ-globin gene mutations. Notably, several mutations are reported for the first time in the Cypriot population, whereas important differences are observed in the distribution of mutations across different districts of the island.

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Familial glomerular hematuria(s) comprise a genetically heterogeneous group of conditions which include Alport Syndrome (AS) and thin basement membrane nephropathy (TBMN). Here we investigated 57 Greek-Cypriot families presenting glomerular microscopic hematuria (GMH), with or without proteinuria or chronic kidney function decline, but excluded classical AS. We specifically searched the COL4A3/A4 genes and identified 8 heterozygous mutations in 16 families (28,1%). Eight non-related families featured the founder mutation COL4A3-p.(G1334E). Renal biopsies from 8 patients showed TBMN and focal segmental glomerulosclerosis (FSGS). Ten patients (11.5%) reached end-stage kidney disease (ESKD) at ages ranging from 37-69-yo (mean 50,1-yo). Next generation sequencing of the patients who progressed to ESKD failed to reveal a second mutation in any of the COL4A3/A4/A5 genes, supporting that true heterozygosity for COL4A3/A4 mutations predisposes to CRF/ESKD. Although this could be viewed as a milder and late-onset form of autosomal dominant AS, we had no evidence of ultrastructural features or extrarenal manifestations that would justify this diagnosis. Functional studies in cultured podocytes transfected with wild type or mutant COL4A3 chains showed retention of mutant collagens and differential activation of the unfolded protein response (UPR) cascade. This signifies the potential role of the UPR cascade in modulating the final phenotype in patients with collagen IV nephropathies.

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BACKGROUND AND OBJECTIVES: A large number of patients with thalassemia major have been born and treated exclusively in Cyprus. They have been managed according to standard international practice, but few have been transplanted. In 1999, a combination chelation regime with desferrioxamine and deferiprone was introduced. We analyzed survival trends in Cypriots and tried to identify factors associated with prolonged survival. DESIGN AND METHODS: We had incomplete information on births pre-1974 and complete information from 1974 onwards. Clinical data were incomplete pre-1980 and complete thereafter. We analyzed data on 539 patients born after 1960 and followed over the period 1980 to the end of 2004. RESULTS: There were 58 deaths, 31 (53.4%) of which where due to cardiac causes. In the complete birth cohort of 284 patients born after 1974, survival (95% CI) at 10, 20 and 30 years was 100% (0); 98.5% (96.1-99.4) and 92.7% (86.7-96.1) respectively. There was a significant trend of increasing cardiac deaths between 1980 and 2000 (p<0.001) and a decline after 2000 (p=0.06). In multivariate survival analysis, protective effects were found for female sex (hazard ratio, 0.37, 95% CI 0.21-0.66; p<0.001), and post-2000 follow-up (hazard ratio, 0.44, 95% CI 0.20-0.99; p<0.05), but not for genotype, treatment center or birth cohort. INTERPRETATION AND CONCLUSIONS: Most patients born after 1974 survive to at least the age of 30. There has been a marked improvement in survival for patients of all ages since 2000, which may be due to the introduction of combination chelation therapy.

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Therapeutic advances in thalassaemia major have significantly increased the average lifespan and improved the quality of life in thalassaemic patients. Therefore attainment of reproductive capacity and creation of a family has become a great task. Endocrine complications due to haemosiderosis and especially hypogonadotrophic hypogonadism are still present in a significant number of patients worldwide and often becomes a barrier in their desire for parenthood. The report of 358 successful pregnancies so far has provided strong evidence not only for the absence of any deleterious effect on the course of thalassaemia but also for the safety of the pregnancy in the thalassaemic woman. Ovarian function is well preserved in women suffering primary or secondary amenorrhea as they become able to conceive following a closely monitored stimulation therapy. The desire of the thalassaemic woman to become a mother is always viewed with special caution and sensitivity. Ambitions of this sort pose numerous medico legal and ethical issues that need to be addressed prudently if the patients' quality of life is to be optimized.

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