Abstract |
This review brings some new insights on erythrocytosis of genetic origin related to problems of oxygen delivery by hemoglobin (Hb). A few molecular mechanisms are individualized among the about 100 Hb variants that cause compensatory erythrocytosis. The most frequently observed structural modifications are localized in the alpha1beta2 interface, or at the C-terminal. They impair formation of a stable T state. Others mutations modify directly or indirectly the surrounding of the heme and the site where oxygen binds. A special interest is brought to the dose effect considering the possibility for formation of hybrid tetramers with altered oxygen binding properties. Homozygous cases, and patients who are compound heterozygotes for a high oxygen affinity Hb and a thalassemia (thal), are discussed. Several examples are provided, specially documented for Hb Olympia [beta20(B2)Val --> Met] and Hb Saint Nazaire [beta103(G5)Phe --> Ile]. Other mechanisms leading to erythrocytosis are discussed, and finally, an algorithm is proposed for etiological diagnosis.
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Authors | Henri Wajcman, Frederic Galactéros |
Journal | Hemoglobin
(Hemoglobin)
Vol. 29
Issue 2
Pg. 91-106
( 2005)
ISSN: 0363-0269 [Print] England |
PMID | 15921161
(Publication Type: Journal Article, Review)
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Chemical References |
- Hemoglobins, Abnormal
- 2,3-Diphosphoglycerate
- Heme
- Oxygen
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Topics |
- 2,3-Diphosphoglycerate
(chemistry, metabolism)
- Genetic Variation
(genetics)
- Heme
(chemistry, metabolism)
- Hemoglobins, Abnormal
(chemistry, genetics, metabolism)
- Humans
- Oxygen
(metabolism)
- Polycythemia
(genetics, metabolism)
- Protein Binding
- Protein Structure, Secondary
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