undergoes polymerization in its deoxygenated form, making red blood vessels cellular

undergoes polymerization in its deoxygenated form, making red blood vessels cellular material stiff and undeformable and causing hemolysis and vaso-occlusion, with injury and pain. 10%(3,4). Right diagnosis of the hemoglobinopathy is really important, particularly through the neonatal period, as early recognition of SCD is fundamental if morbidity and mortality of these diseases are AP24534 cost to be reduced. Laboratory diagnosis of SCD generally involves techniques based on the electric charge of the variants, such as cellulose acetate or gel electrophoresis, isoelectric focusing, high-performance liquid chromatography (HPLC) and capillary electrophoresis(5). However, as more than 1,000 variants have been described to date(6), the probability of finding another variant with electrophoretic behavior similar to that of Hb S (Hb S-like hemoglobins) is quite high, particularly in a population with a high degree of miscegenation, like that of Brazil. For this reason it is important to use confirmatory tests (which are also frequently used in screening programs), such as the sickling test and the hemoglobin solubility test (based on the insolubility of deoxy-HbS in high molarity phosphate buffer)(5). In the case of Hb S in association with other variants, whether Hb S-like or AP24534 cost not, correct identification of the second variant is fundamental to distinguish between those variants that will lead to SCD, those that evolve without any symptoms and those that produce specific symptoms(7). Molecular techniques, such as restriction enzyme analysis and globin gene sequencing, are the most commonly used techniques for known mutations and new or rare mutations, respectively(8,9). It should also be mentioned that some Hb S-like variants can cause red blood cell sickling, hemolysis and vaso-occlusion even in a heterozygous state. Examples include Hb Jamaica Plain(10) and Hb S S?o Paulo(11), the latter recently described in the Brazilian population. It should also be stressed that Hb S in association with an Hb S-like hemoglobin can lead to an incorrect diagnosis of SCA if the appropriate confirmatory tests are not carried out(12). And what are the Hb S-like variants in the Brazilian population? Some variants have a structural change in the -chains, AP24534 cost while in others the -chains are affected. The previous consist of Hbs D, Lepore, Korle-Bu, Osu-Christiansborg and Zrich(13,14), and the latter Hbs SERPINA3 Hasharon, Stanleyville-II, G-Pest, Sunshine Seth, G-Philadelphia, West One and Daneshgah-Tehran(8,9,14). Regarding the -chain variants, some technical features might help with the analysis; these include the current presence of four bands in electrophoresis – two corresponding to Hb A2 (A2 and A2′) and two to Hb A (A and ‘X’) – and a lesser focus of ‘Hb X’ than normally seen in people with -chain variants. Some -chain AP24534 cost variants are connected with -thalassemia, with concomitant microcytosis and hypochromia, as may be the case with the Hasharon (Figure 1) and Stanleyville-II variants, the most typical in the Brazilian inhabitants(8,15). Open up in another window Figure 1 (a) Cellulose acetate electrophoresis at alkaline pH; (b) restriction evaluation with Taq I to verify Hb Hasharon Analysis through the neonatal period, nevertheless, involves further issues: the reduced focus of -chain variants helps it be difficult to start to see the bands obviously, and the high focus of fetal Hb (Hb F) inhibits confirmatory testing. The mostly used screening strategies in Brazil are isoelectric concentrating and HPLC, accompanied by molecular biology methods(16). In the National Neonatal Screening System managed by the Brazilian nationwide health program (SUS), the back heel prick, which can be carried out generally in most Brazilian maternity wards, can be used to display for SCD and additional genetic diseases(1). Using this screening system numerous -chain variants have already been detected, as this article released in this problem by Silva et al.(17), owned by the research band of Prof. Marcos Borato Viana, of the of the Pediatrics Division of the Universidade Federal government de Minas Gerais (UFMG), displays us. The neonatal screening system operate by the Nucleus of Activities and Study in Diagnosis as of this university offers helped to supply a greater knowledge of the hemoglobinopathies within different parts of Brazil – AP24534 cost each one using its personal ethnical features and diversity – and offers highlighted the need for screening alone and of properly identifying additional variants that can be confused with Hb S. Footnotes Conflict-of-interest disclosure: The author declares no competing financial interest.

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