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We report a novel hemoglobin (Hb) variant found in a Spanish individual from Santa Cruz de Tenerife, the Canary Islands in Spain. The proband was a 39-year-old male. High performance liquid chromatography (HPLC) displayed an unknown peak (19.3%) at a retention time of 1.3 min. eluting before Hb A 0 . Capillary zone electrophoresis (CZE) showed an abnormal peak (20.0%) in zone 12. Direct DNA sequencing of the α-globin genes revealed heterozygosity for a nonsense mutation at codon 139 ( A AA> T AA), causing a lysine to stop codon substitution [α139(HC1)Lys→Stop; HBA1 : c.418A>T]. We decided to name the variant Hb Nivaria (Tenerife) for the place of birth and residence of the proband.

Background and Aims: Hereditary anemia (HA) encloses a wide group of rare inherited disorders with clinical and hematologic overlaps that complicate diagnosis., Materials and Methods: A 48-gene panel was developed to diagnose HA by Next Generation Sequencing (NGS) in a large cohort of 165 patients from 160 unrelated families., Results: Patients were divided in: A) patients who had a suspicion of a specific type of HA (n = 109), and B) patients who had a suspicion of HA but with no clear type (n = 56). Diagnostic performance was 83.5% in group A and a change of the initial diagnosis occurred in 11% of these patients. In group B, 35.7% of patients achieved a genetic diagnosis. NGS identified 6 cases of xerocytosis, 6 of pyruvate kinase (PK) deficiency, 4 of G6PD, and 1 case of phytosterolemia with no initial suspicion of these pathologies, which is clinically relevant since they have specific treatment. Five patients were found to carry variants associated to two different pathologies (4 of them combining a metabolic deficiency and a membrane defect), and 44 new variants were identified in 41 patients., Conclusion: The use of NGS is a sensitive technique to diagnose HA and it shows better performance when patients are better characterized., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background and Objective: The glycated hemoglobin (HbA1c) test by high performance liquid chromatography is a useful tool for the follow-up of diabetes mellitus patients. Some structural hemoglobin (Hb) variants are known to cause interference in the analytical measurement of HbA1c., Patients and Methods: In this study, it has been characterized a new Hb variant in 4 patients during their regular control of HbA1c., Results: Selective α1 gene sequencing showed a mutation GAC>AAC at codon 64 within exon 2. This produces a change of aspartic acid (Asp) by asparagine (Asn) that does not produce any functional alteration so the resultant molecule behaves as a silent hemoglobinopathy., Conclusion: The structural Hb variants can be detected during the analysis of HbA1c and may alter its values. Though rare, this occurrence signals the need to being aware when measuring HbA1c., (Copyright © 2014 Elsevier España, S.L.U. All rights reserved.)

Background: In the last decade immigration to Europe has increased, with Africa being the source of a large number of immigrants. In addition to infections, this group has other less known health problems, such as erythrocyte abnormalities., Methods: The objectives of this study were: the systematic evaluation of red cell abnormalities in 200 newly arrived asymptomatic African immigrants on the Canaries; the systematic evaluation of haemoglobinopathies and their characterization in this population; and the relationship of red blood cell disorders and parasitic infections., Results: Of the studied immigrants 53 (26.5%) had red cell disorders according to their CBC parameters (Hb and/or MCV). In 48 people (24.0%) one or more etiologic diagnoses were made. Specifically, in order of frequency, a total of 26 structural haemoglobinopathies, 14 α-thalassemias, 2 β-thalassemias and 14 iron deficiencies were diagnosed. There was a statistically significant association between the presence of anemia, microcytosis, structural haemoglobinopathies or α thalassemia and sub-Saharan origin. However, no statistically significant association between the abovementioned parameters and eosinophilia or helminthic infection was observed., Conclusions: These results suggest that, even in the presence of normal Hb and MCV values, including haemoglobinopathies in the initial screening of newly arrived sub-Saharan immigrants would be very useful.

Objectives: The aim of the study was to investigate hemoglobin (Hb) species in a 61 year-old male with diabetes mellitus type II and a low value of Hb A(1c)., Design and Methods: Hb species were analyzed by electrophoresis and chromatography methods. Functional properties were determined by oxygen equilibrium studies. β-globin gene was amplified by PCR and sequenced., Results and Conclusions: A novel clinically silent Hb (Hb Seville), that results in falsely low Hb A(1c) measurement, was detected. This Hb variant presented a single base mutation at codon 81 (C→T) of the β-globin gene. This case points out the necessity of careful inspection of the chromatograms and the use of additional methods to Hb A(1c) measurement when the presence of aberrant peaks is detected., (Copyright © 2011 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

The alpha thalassaemia diseases in most cases are caused by deletions that affect one or two of the alpha genes, being less frequent the cases due to punctual mutations, insertions or deletions of a few pairs of bases, which have been denominated no deletion a thalassaemias. The objective of this investigation was to determine the incidence of the no deletion alpha thalassaemia in patients with a thalassaemia using molecular biology techniques. We studied 517 individuals of the San Carlos Hospital (Thalassemia Molecular Research Center, Madrid-Spain) between January 2001 and December 2003, in whom iron deficiency anemia had been ruled out, that presented microcytosis and hypochromia and that presented normal HbA2, HbF and EEF from normal Hbs. The two types of no deletion a thalassaemia most frequently described in the Mediterranean were studied: 1) alpha Hph due to deletion of 5bp in the IVS I and 2) alphaNco due to a change in the initiation codon of the gene. Of the 517 cases studied, 40 (7.7% of the cases) represented a no deletion alpha thalassaemia. Of these cases, 28 were positive for alphaHph of the alpha2 gene, 24 in the heterozygote state, one homozygote and three double heterozygotes associated with the 3,7 kb deletion. The remaining 12 cases were positive for the alphaNco of the alpha2 gene, 10 heterozygotes, one homozygote and one double heterozygote associated with the 4,2 kb deletion. The no deletion alpha thalassaemias represent < 8% from the cases in our environment. The alphaHph is the most frequent type of no deletion a thalassaemia and its haematological abnormalities are more manifest that the ones present in the cases of alphaNco.

Background and Objective: The aim of this study was to determine the molecular defects of heterozygous beta thalassaemia and to ascertain their distribution in Lanzarote., Patients and Method: Molecular characterization was achieved by real time polymerase chain reaction (RT-PCR LightCycler, Roche), PCR-ARMS (PCR-amplification reaction mutations system) and DNA sequencing on an automated DNA sequencer., Results: Two hundred forty-three heterozygous beta thalassaemia carriers were included between July 1991 and February 2007. RT-PCR detected the molecular defect in 81% of the beta thalassaemia chromosomes analyzed [113 codon CD 39 (C --> T); 41 IVS-1-nt-110 (G --> A), 25 IVS 1-nt-1 (G --> A) and 19 IVS 1-nt-6 (T --> C)]. The remaining 12 molecular defects included the deletion 619 bp (7.8%) and the mutations -28 (A --> G), IVS1-nt-2 (T --> G), CD 41/42 (-TTCT), CD 8/9 (+G), CD 51 (-C), CD 22 (G --> T) and CD 24 (T --> A), CD 67 (-TG) and the novel mutation CD 20/21-TGGA., Conclusions: The distribution of the mutations is similar to that found in the Mediterranean area. The increasing migratory flow received in the Canary Islands may explain the emergence of new mutations not reported before in our area.

Background: The aim of this study is to analyze the global prevalence of carriers of heterozygous hemoglobinopathies among pregnant women settled in Lanzarote., Patients and Methods: A epidemiologic cross-sectional observational investigation was undertaken to study the prevalence of hemoglobinopathies in 2,436 pregnant women in Lanzarote. The techniques of primary screening were hemoglobin electrophoresis on cellulose acetate at alkaline pH for the detection of hemoglobin variants, and the quantification of HbA2 and HbF for the diagnosis of b thalassemia trait. The study to confirm the diagnosis of structural hemoglobinopathies was based on hemoglobin electrophoresis on citrate agar at acid pH, isolectric focusing and high-performance liquid chromatography (HPLC). The molecular characterization of b thalassemia trait (HbA2 >3.5%) was carried out by techniques using a real time PCR procedure with specific fluorescently labelled hybridization probes and allele-specific amplification (PCR-ARMS)., Results: The global prevalence of hemoglobinopathies was 11.90 corresponding to 9.44 for structural hemoglobinopathies and 2.46 for heterozygous b thalassemias. A variant hemoglobin was detected on 23 women and the distribution was as follows: thirteen carriers of hemoglobin S, seven HbC trait, two HbD trait and one "unstable" hemoglobin. 82.6% of the variant hemoglobins found were from migrant population from Africa and America., Conclusions: The high prevalence of carriers of structural hemoglobinopathies in Lanzarote justifies the initiation of programs for screening for hemoglobinopathies to prevent the emergence of severe states causing disease.