Of hemoglobin variants

Manning JM et aJ Normal and abnormal protein subunit interactions in hemoglobins.] Biol Chem 1998 273 19359-Mario N, Baudin B, Giboudeau J Qualitative and quantitative analysis of hemoglobin variants by capillary isoelectric focusing. J Chromatogr B Biomed Sci Appl 1998 706 123-Reed W, Vichinsky EP New considerations in the treatment of sickle cell disease. Annu Rev Med 1998 49 46l. 

The detection of abnormal hemoglobins In cord blood samples Is usually made with electrophoretic procedures. Four types of hemoglobin variants can be present, namely y-chaln variants, 3-chaln variants, and Hb-Bart s or yif Indicating some form of a-chaln deficiency or a-thalassemla. 

Structural Analyses of Hemoglobin Variants It has become Impossible to characterize nearly any abnormal hemoglobin by Its electrophoretic and/or chromatographic mobility only This Is most strikingly demonstrated by the fact that over fifty different variants behave similar to Hb-S In electrophoresis Characterization, therefore, often requires detailed structural analyses or the demonstration of a property unique to a specific variant Some of the techniques used In these studies will be... 

The reversed-phase HPLC separation of the tryptic peptides of hemoglobin variants using ammonium acetate buffers, generally 10 mM at pH... 

An improved procedure for the preparation of stable anion exchangers on porous microparticulate silicas has been described by Regnier and co-workers 232), These and related supports have found application in the profiling of hemoglobin variants and for peptide separation 236-239). 

Reviews on hemoglobinopathies often contain a detailed description of studies pertaining to the distribution of hemoglobin variants the most comprehensive review has been given by F. B. Livingstone (L30). 

H59. Huisman, T. H. J., Schroeder, W. A., Bouver, N., Miller, A., Shelton, J. R., Shelton, J. B., and Apell, G., Chemical heterogeneity of fetal hemoglobin in subjects with sickle cell anemia, homozygous Hb-C disease, SC-disease, and various combination of hemoglobin variants. Clin. Chim. Acta 38, 5-16 (1972). 

Capillary isoelectric focusing coupled to mass spectrometry has gained popularity in recent years (by analogy to two-dimensional gel electrophoresis). Additional information obtained from mass spectrometry includes not only precise molecular-weight determination but also the possiblity for peptide sequencing. Analysis of hemoglobin variants, recombinant proteins, and monoclonal antibodies have been demonstrated [1,7,8]. 

Bry L, Chen PC, Sacks DB. Effects of hemoglobin variants and chemically modified derivatives on... 

Fairbanks V. Tables of hemoglobin variants. In Fairbanks VF, ed. Hemoglobinopathies and Thalassemias. New York BC Decker, 1980 247-260. 

Gerritsma, Sinnige D, Drieze C, Sittrop B, Houtsma P, Hulshort-Jansen N, Huisman W. Quahtative and quantitative analysis of hemoglobin variants using capillary zone electrophoresis. Ann Clin Biochem 2000 37 380-9. 

Hempe JM, Graver RD. Separation of hemoglobin variants with similar change by capillary isoelectric focussing value of isoelectric point for identification of common and uncommon hemoglobin variants. Electrophoresis 2000 21 738-43. 

Mario N, Baudin B, Aussel C, Giboudeau J. Capillary isoelectric focussing and high-performance cation-exchange chromatography compared for qualitative and quantitative analysis of hemoglobin variants. Clin Chem 1997 43 2137-42. 

Ou C-N, Rognerud CL. Rapid analysis of hemoglobin variants by cation-exchange HPLC. Clin Chem 1993 39 820-4. 

Rioux, Godart C, Huntrel D, Mathis M, Bimet C, Bardakjian J, et al Cation-exchange HPLC evaluated for presumptive identification of hemoglobin variants. Clin Chem 1997 43 34-9. 

Watanabe T, Kato K, Yamada D, Midorikawa S, Sato W, Shiga M, et al. A nondiabetic case of hemoglobin variant (Hb Nigata) with inappropriately high and low HbAic titers detected by different methods. Clin Chem 1998 44 1502-4. 

Figure 1. The separation of hemoglobin variants by classical LC(1) and by modern HPLC (2) techniques.

The most important applications of electrophoresis are in molecular biology and medicine where, for example, the study of inherent variabilities of serum proteins has produced a new branch of genetics, and the discovery of hemoglobin variants in several anemias has introduced the notion of molecular diseases. Electrophoresis has also greatly facilitated sequencing of nucleic acids, the clinical diagnosis of protein dyscrasias, the measurement of isoenzyme distribution, and the classification of lipoproteinemias, among others. 

Li M X, Liu L, Wu J T, et al. (1997). Use of a polybrene capillary coating in capillary electrophoresis for rapid analysis of hemoglobin variants with on-line detection via an ion trap storage/reflectron time-of-flight mass spectrometer. Analyt. Chem. 69 2451-2456. 

Lillard, S. J. Yeung, E. S. Lautamo, R. M. Mao, D. T. Separation of hemoglobin variants in single human erythrocytes by capillary electrophoresis with laser-induced native fluorescence detection. J. Chromatogr. A 1995, 718, 397 04. 

Frequencies of Hemoglobin Variants Thalassemia, The Glucose-6-Phosphate Dehydrogenase Deficiency, G6PD Variants, and Ovalocytosis in Human Populations... 

Hempe, J.M., and Craver, R.D. Quantification of hemoglobin variants by capillary isoelectric focusing. 

Figure 2 Typical separation of hemoglobin variants using cellulose acetate electrophoresis. Track 1 is a standard mixture of HbA and HbS, tracks 2, 4, 7, 8, 10, 11,13 are normals tracks 5 and 6 are HbC traits tracks 9, 12, 14 are HbS traits and track 3 is HbS/HbC disease. (Reproduced with permission from the Department of Haematology, King s College Hospital, London.)...

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