General information
Globin chain involved
Status
Heterozygous
Migration zones
Migration positions
162, 171
Sickle Cell Disease: No
Thalassemic variant: No
Capillary Electrophoresis
Fractions
Value %
Denatured Hb
9.7
Hb A
59.8
Hb Ypsilanti
4.4
Hb Ypsilanti
19.6
Hb A2
6.5
Comments
Hb A2 is overestimated due to partial loss of integration of Hb A and the two peaks of Hb Ypsilanti. It is recommended to delete the automatic quantification of these peaks and then manually quantify them together to obtain a correct estimate of Hb A2 (here 2.3%).
Mutation data
Heterozygous Hb Ypsilanti
Mutation
HGVS Nomenclature
Beta 99(G1) Asp>Tyr
HBB:c.298G>T
Hematological parameters
Name
Result
RBC Count
Elevated
Total Hemoglobin
Elevated
MCV
Normal
MCH
Normal
Blood smear
No information
Other analysis
Normal MCHC, elevated to very elevated hematocrit
Comments on hematology
Erythrocytosis
Clinical context
Clinical presentation
Normal
Clinical risk
No data
Variant information
Stability
Polymerizes
Oxygen affinity
Increased
Ethnicities in literature
Found in Black African populations and, more rarely, Middle East & Asian populations: met in 17 members in three generations of a Black family living in the USA, in two diabetic patients from Malaysia, in a 51-year-old woman and her 24-year-old daughter living in Denmark, and in a 53-year-old male living at high altitude in Saudi Arabia
Comments on variant information
The rare variant Hb Ypsilanti tends to polymerize, leading to the appearance of two peaks in different proportions.
Scientific Literature
Scientific references
- https://pubmed.ncbi.nlm.nih.gov/5687529/ Glynn K.P. et al., Ann Intern Med. 1968 Oct;69(4):769-76.
- https://pubmed.ncbi.nlm.nih.gov/10194373/ Huang J. et al., Biochemistry. 1999 Apr 6;38(14):4514-25.
- https://pubmed.ncbi.nlm.nih.gov/17951209/ Mais D.D. et al., Am J Clin Pathol. 2007 Nov;128(5):850-3.
- https://pubmed.ncbi.nlm.nih.gov/24371790/ Nygaard M. et al., Leuk Res Rep. 2013 Oct 9;2(2):86-8.
- https://pubmed.ncbi.nlm.nih.gov/24614705/ Sthaneshwar P. et al., Pathology. 2014 Apr;46(3):263-5.
- https://pubmed.ncbi.nlm.nih.gov/29365076/ Riou J. et al., Am J Clin Pathol. 2018 Jan 29;149(2):172-180.
- https://journals.lww.com/jaht/fulltext/2023/14040/first_observation_of_hemoglobin_ypsilanti_in_saudi.13.aspx Alkhaldy H. et al., Journal of Applied Hematology 14(4):p 331-334, Oct–Dec 2023.
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
In some cases (homozygotes, combination of the variant with thalassemia, transfused patients, degraded samples or unstable variants), the variation in the migration position may be greater than +/- 1 point.
For profiles with thalassemia, only Hb A2 and Hb F peaks, if present, are listed with 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.
Hematological Parameters