Over the past few years, the methodologies used for the identification of hemoglobin A variants have been greatly improved. Both the protein- and DNA-based strategies have their own advantages and limitations. In this report we illustrate the use of both assays for the characterization of a hemoglobin Cocody variant in a woman of Spanish descent. After evaluating the mobility value matrix of the abnormal hemoglobin, the amino acid transition was determined by HPLC and microsequencing of the protein. Theβ 21 Asp was shown to be substituted by an Asn. At the DNA level, the only nucleotide replacement responsible for this amino acid substitution is GAT- → AAT at codon 21. The analysis of theβ-globin gene by denaturing gradient gel electrophoresis (DGGE) method showed that the mutation was situated in a fragment including exon 1. The hemoglobin variant was then identified to be hemoglobin Cocody by DNA sequencing of this fragment.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Atree O, Vidaud M, Vidaud D, Amselem S, Lavergne J, Goossens M (1989) Mutations in the catalytic domain of human coagulation factor IX: rapid characterization by direct genomic sequencing of DNA fragments dysplaying an altered melting behavior. Genomics 4: 266–272
Basset P, Beuzard EF, Garel MC, Rosa J (1978) Isoelectric focusing of human hemoglobin: its application to screening, to characterization of 70 variants, and to the study of modified fractions of normal hemoglobin. Blood 51: 971–982
Boissel JP, Wajcman H, Cabannes R, Labie D (1981) Application of high-performance liquid chromatography to abnormal hemoglobin studies. Characterization of hemoglobins D in Ivory Coast and description of a new variant Hb Cocody (β 21 (B3) Asp- → Asn). Biochim Biophys Acta 670: 203–206
Cai SP, Kan YW (1990) Identification of multipleβ-thalassemia mutations by denaturing gradient gel electrophoresis. J Clin Invest 85: 550–553
Ghanem N, Girodon E, Vidaud M, Martin J, Fanen P, Plassa F, Goossens M (1992) A comprehensive scanning method for rapid detection ofβ-globin gene mutations and polymorphisms. Hum Mutation 1: 229–239
Gyllensten UB, Erlich HA (1988) Generation of single-stranded DNA by polymerase chain reaction and its application to direct sequencing of the HLA-DQ-A locus. Proc Natl Acad Sci USA 85: 7652–7656
International Hemoglobin Information Center Variants List (1992) Hemoglobin 16: 2–118
Lacombe C, Riou J, Godard C, Rosa J, Galacteros F (1986) Characterization approach of “silent” beta chain hemoglobin variants. Acta Haematol 78: 119–122
Losekoot M, Foode R, Harteveld CL, Heeren HV, Giordano PC, Bernini LF (1990) Denaturing gradient gel electrophoresis and direct sequencing of PCR-amplified genomic DNA: a reliable diagnostic approach to beta thalassaemia. Br J Haematol 76: 269–274
Maniatis T, Fritsch EF, Sambrook J (1982) Molecular cloning laboratory manual. Cold Spring Harbor Laboratory, New York
Myers R, Maniatis T, Lerman L (1987) Detection and localization of single base changes by denaturing gradient gel electrophoresis. Methods Enzymol 155: 501–527
Saiki RK, Bugawan TL, Horn GT, Mullis KB, Erlich HA (1986) Analysis of enzymatically amplifiedβ-globin and HLA-DQa DNA with allele-specific oligonucleotide probes. Nature 324: 163–166
Schneider RG, Barwick RC (1986) Electrophoretic mobilities of mutant hemoglobins and mutant globin chains. CRC Handbook Series in Clinical Laboratory Science. Sect. I: Hematology, vol IV. CRC Press, Boca Raton, FL
Vidaud M (1990) Applications de la génétique moléculaire à l'étude et au diagnostic des maladies héréditaires. A propas desβ-thalassémies et de l'hémophilie B. Thèse de doctorat de l'Université Paris VII, Paris
Vidaud M, Fanen P, Martin J, Ghanem N, Nicolas S, Goossens M (1990) Three-point mutations in the CFTR gene in French cystic fibrosis patients: identification by denaturing gradient gel electrophoresis. Hum Genet 85: 446–449
About this article
Cite this article
Aguilar-Martinez, P., Galacteros, F., Schved, J.F. et al. Comparison of the protein and DNA approaches for the characterization of a β-globin chain variant, hemoglobin Cocody [β21 (B3) Asp- → Asn], in a Caucasian patient. Ann Hematol 66, 269–272 (1993). https://doi.org/10.1007/BF01738480
- Hemoglobin Cocody
- Denaturing gradient gel electrophoresis
- β-Globin protein characterization