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The fate of excess β ‐globin chains within erythropoietic cells in α ‐thalassaemia 2 trait, α ‐thalassaemia 1 trait, haemoglobin H disease and haemoglobin Q‐H disease: an electron microscope study
Author(s) -
Wickramasinghe S. N.,
Hughes Madeleine,
And S. Fucharoen,
Wasi P.
Publication year - 1984
Publication title -
british journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.907
H-Index - 186
eISSN - 1365-2141
pISSN - 0007-1048
DOI - 10.1111/j.1365-2141.1984.tb03977.x
Subject(s) - proteolysis , reticulocyte , erythroblast , ineffective erythropoiesis , bone marrow , alpha (finance) , globin , chemistry , electron microscope , medicine , hemoglobin , biology , anemia , biochemistry , erythropoiesis , gene , rna , physics , surgery , construct validity , patient satisfaction , enzyme , optics
S ummary . Electron microscope studies have been performed on bone marrow cells from individuals with various α ‐thalassaemia syndromes. Globin chain precipitates were rarely found in the erythropoietic cells of a subject with α ‐thalassaemia 2 trait. By contrast, such precipitates were found in 0.6–1.3% of the erythroblast and marrow reticulocyte profiles in two cases of α ‐thalassaemia 1 trait, 2.1–13.7% of profiles in five patients with haemoglobin H (HbH) disease and 6.2% of profiles in one patient with haemoglobin Q‐H (HbQ‐H) disease. In the patient with HbQ‐H disease, but not in the others, the nuclei of some erythroblasts displayed the ‘Swiss cheese’appearance which has been reported in some forms of congenital dyserythropoietic anaemia. It is proposed that in α ‐thalassaemia 2 trait, where the degree of excess of β ‐chains is slight, most of the excess chains are degraded by proteolysis. In α ‐thalassaemia 1 trait, where there is a greater excess of β ‐chains, the excess chains can undergo either proteolysis or precipitation, but there is little or no tetramerization to form soluble HbH. Finally, in HbH disease, where the degree of excess is considerable, the excess β ‐chains may be subject to proteolysis, precipitation and tetramerization.