Balearic archipelago: three islands, three beta-thalassemia population patterns.

The mutation spectrum of 175 ß-thalassemia (ß-thal) carriers, identified in pilot carrier screening on 22,713 individuals from Balearic Islands (Spain), is reported. The ß(0) CD39 (C>T) mutation is the most frequent (61.1%), followed by ß(+) IVS-I-110 (G>A) (12.0%), ß(+) IVS-I-6 (T>C) and ß(0) IVS-1-1 (G>A) (3.4% both) and eight other rare mutations (2.9-0.6%); with a distinct prevalence and distribution between islands. Minorca shows the highest prevalence in Iberian populations, with a single mutation, CD39 (C>T), present in most ß-thal carriers. Ibiza is the only Western Mediterranean population where the most frequent ß-thal mutation is IVS-I-110 (G>A). These results can be explained by a combination of historical-demographic characteristics together with evolutionary forces such as founder effect, genetic drift and probably selection by malaria. Knowledge of the mutational spectrum in the Balearic Islands will enable to optimize mutation detection strategy for genetic diagnosis of ß-thal in these islands.

Cribado neonatal de anemia falciforme en la Comunidad Autónoma Balear. Estudio piloto anónimo no relacionado / Neonatal screening of sickle cell disease in the Balearic Islands Autonomous Community. Pilot study in anonymous unrelated population

Introducción: La anemia falciforme, fenotipo FS, es la más común de las hemoglobinopatías estructurales. Es un trastorno hereditario causado por la presencia de hemoglobina S (HbS), resultado de una mutación puntual que afecta al codón 6 de la cadena betaglobina. En condiciones de hipoxia, se produce la polimerización de la HbS y da lugar a crisis vasoclusivas y a anemia hemolítica. Debido a que los fenómenos de inmigración han aumentado considerablemente en España y a que la mayoría de los inmigrantes pertenecen a poblaciones de riesgo para distintas hemoglobinopatías, nuestro objetivo es determinar la incidencia de la anemia falciforme y de otras hemoglobinopatías estructurales en los recién nacidos de esta Comunidad Autónoma (Islas Baleares), mediante un estudio piloto no relacionado y evaluar la necesidad de incluir esta enfermedad dentro del programa de cribado neonatal. Material y métodos: Para esto, se ha utilizado el mismo espécimen de sangre capilar usado para la detección precoz de hipotiroidismo congénito, fenilcetonuria y fibrosis quística. La separación de variantes de hemoglobina (Hb) se llevó a cabo mediante cromatografía líquida de alta resolución y se utilizó el sistema automático Variant® (Bio-Rad). Resultados: La incidencia global de variantes de Hb ha sido de 9,9 por cada 1.000 recién nacidos analizados, con una incidencia de anemia falciforme (fenotipo FS) de uno cada 6.756 casos analizados y de portadores (fenotipo FAS) de uno cada 199 casos. Conclusiones: Tanto la tasa global de variantes observadas como la incidencia de rasgo falciforme justifican plantearse la inclusión del estudio de hemoglobinopatías en el programa de cribado neonatal de la Comunidad (AU)

Introduction: Sickle cell disease (SCD) describes a group of inherited disorders caused by the presence of the sickle haemoglobin (HbS) which results from a point mutation affecting codon 6 of the â globin chain (â codon 6, Glu 6 Val).The pathophysiology involves polymerisation of HbS under low oxygen conditions causing vaso-occlusion and chronic haemolysis and anaemia. Due to increase in immigrants within our population and the majority of this group being a risk population for different haemoglobinopathies, the aim of our study is to determine the incidence of SCD and others structural haemoglobinopathies in the neonatal population of the Balearic Islands Autonomous Community, by means of an unrelated pilot study and determine the need to include this pathology in a newborn screening program. Material and methods: The study was performed with the same blood spot specimen dried on filter paper used for congenital hypothyroidism, phenylketonuria and cystic fibrosis screening. High-performance liquid chromatography (HPLC), using the VARIANTs (Biorad) automated system, was used to detect variants haemoglobin variants. Results: The overall incidence was 9.9 per 1000 specimens. The incidence of SCD was 1/6756 (FS) and the incidence of sickle cell traits was 1/199 (FAS). Conclusion: These results confirm the need to include screening for SCD and other haemoglobinopathies in our neonatal screening program (AU)

[Neonatal screening of sickle cell disease in the Balearic Islands Autonomous Community. Pilot study in anonymous unrelated population]. / Cribado neonatal de anemia falciforme en la Comunidad Autónoma Balear. Estudio piloto anónimo no relacionado.

INTRODUCTION: Sickle cell disease (SCD) describes a group of inherited disorders caused by the presence of the sickle haemoglobin (HbS) which results from a point mutation affecting codon 6 of the beta globin chain (beta codon 6, Glu 6 Val). The pathophysiology involves polymerisation of HbS under low oxygen conditions causing vaso-occlusion and chronic haemolysis and anaemia. Due to increase in immigrants within our population and the majority of this group being a risk population for different haemoglobinopathies, the aim of our study is to determine the incidence of SCD and others structural haemoglobinopathies in the neonatal population of the Balearic Islands Autonomous Community, by means of an unrelated pilot study and determine the need to include this pathology in a newborn screening program. MATERIAL AND METHODS: The study was performed with the same blood spot specimen dried on filter paper used for congenital hypothyroidism, phenylketonuria and cystic fibrosis screening. High-performance liquid chromatography (HPLC), using the VARIANTs (Biorad) automated system, was used to detect variants haemoglobin variants. RESULTS: The overall incidence was 9.9 per 1000 specimens. The incidence of SCD was 1/6756 (FS) and the incidence of sickle cell traits was 1/199 (FAS). CONCLUSION: These results confirm the need to include screening for SCD and other haemoglobinopathies in our neonatal screening program.

Clinical disease activity and titers of anti-dsDNA antibodies measured by an automated immunofluorescence assay in patients with systemic lupus erythematosus.

Autoantibodies specific for double stranded DNA (anti-dsDNA Abs) are a serological biomarker of systemic lupus erythematosus (SLE) and constitute useful tools for monitoring many SLE patients. A new automated immunofluorescence and quantitative assay (EliA dsDNA) has recently become available. Its performance has been demonstrated to be equivalent to the Farr and Crithidia luciliae fluorescence (CLIFT) tests. The aim of the present work was to assess the utility of this new assay to monitor clinical activity in a large cohort of SLE patients. To this end, 1020 sera from 181 SLE patients were evaluated by the two methods. Results showed a higher frequency of positive results of anti-dsDNA Abs during lupus flares measured by EliA dsDNA than by CLIFT. Likewise, titers of those Abs were significantly increased in active SLE in comparison with inactive SLE when measured by EliA dsDNA but not by CLIFT. Serum titers of anti-dsDNA Abs by both assays showed a significant negative association with concentrations of C3 and C4. In summary, this retrospective study on a large cohort of patients demonstrated that EliA dsDNA was at least as useful as CLIFT as monitoring tool in the follow-up of SLE patients, but with the advantages of being automated, quick and quantitative.