General information
Globin chain involved
Status
Heterozygous
Migration zones
Migration positions
150, 203, 221
Sickle Cell Disease: No
Thalassemic variant: No
Capillary Electrophoresis
Fractions
Value %
Denatured Hb
2.6
Hb A + Hb Djelfa
90.5
Hb F
1.0
Derivates
0.5
Derivates
2.2
Hb A2
3.2
Comments
The mild instability of the rare variant Hb Djelfa leads to the appearance of several minor peaks.
Mutation data
Heterozygous Hb Djelfa
Mutation
HGVS Nomenclature
Beta 98(FG5) Val>Ala
HBB:c.296T>C
Hematological parameters
Name
Result
RBC Count
No information
Total Hemoglobin
No information
MCV
No information
MCH
No information
Blood smear
Heinz bodies
Other analysis
No information
Comments on hematology
Reticulocytosis
Clinical context
Clinical presentation
Moderate anemia symptoms
Clinical risk
Risk for consistent hemolysis in combination with beta-thalassemia
Variant information
Stability
Mildly unstable
Oxygen affinity
Increased
Ethnicities in literature
Found in Caucasian populations: met in two unrelated French Caucasian adults but not in their parents. Presumably a de novo mutation
Comments on variant information
The rare variant Hb Djelfa is one the five unstable variants of a substitution located at position FG 5, the other four being Hb Köln, Hb Nottingham, Hb Phou Bia and Hb Mainz.
Scientific Literature
Scientific references
- https://pubmed.ncbi.nlm.nih.gov/1225587/ Gacon G. et al., FEBS Lett. 1975 Oct 15;58(1):238-40.
- https://pubmed.ncbi.nlm.nih.gov/13850/ Gacon G. et al., Biochim Biophys Acta. 1977 Jan 25;490(1):156-63.
- https://pubmed.ncbi.nlm.nih.gov/2737917/ Bird AR. et al., Hemoglobin. 1989;13(2):193-7.
- https://pubmed.ncbi.nlm.nih.gov/10081988/ Lacan P. et al., Hemoglobin. 1999 Feb;23(1):73-7.
- https://pubmed.ncbi.nlm.nih.gov/29365076/ Riou J. et al., Am J Clin Pathol. 2018 Jan 29;149(2):172-180.
Globin Chain involved
Status
The term "Double Heterozygous" refers to cases of heterozygosity on different globin chain types, while the term "Compound Heterozygous" refers to cases of heterozygosity on the same globin chain type.
For example, S/G-Pest is a Double Heterozygous case (beta and alpha-globin chains are mutated) and S/C is a Compound Heterozygous case (only beta-globin chains are mutated).
Migration zones
Migration positions
Sickle Cell Disease
Thalassemic variant
Capillary Electrophoresis
Variant information
Ethnicities are provided for informational purposes only and are based on scientific literature and conference posters.
A hemoglobin variant may therefore be present in populations of ethnic origins or countries not listed here.