[Analysis of the relative rates of synthesis of G gamma and A gamma globin chains in the erythropoietic bursts in patients with trisomy 13 syndrome].
To clarify the pathogenesis of fetal-like erythropoiesis including high levels of Hb F observed in trisomy 13 syndrome, we examined the biosynthesis rates of G gamma and A gamma globin chains in the erythropoietic bursts cultured from the peripheral blood mononuclear cells of 3 patients aged 1-month-, 2-month and 7-month-old. Globin chains were labeled with 14C-amino acids, separated by isoelectric focusing and quantitated by autoradiography. The synthesis rates of gamma-chains in the erythropoietic bursts were between 83% and 88%. The Gr:A gamma ratios were similar to the synthesis ratio (0.71) of fetal liver BFU-E (12-wk gestation). Furthermore, the G gamma values in the bursts of the patients were in agreement with the G gamma:A gamma ratios in their circulating red blood cells (0.70, 0.71 and 0.67). These results suggest that the erythropoiesis associated with high levels of Hb F in trisomy 13 syndrome is controlled by erythropoietic precursor cells, in which normal switchings of G gamma:A gamma ratio and from Hb F to Hb A have not occurred.
Sasaki
H
H
Matsuda
M
M
Terasawa
T
T
Ito
T
T
Fukushima
Y
Y
Kuroki
Y
Y
Matsuyama
S
S
D000409:Alanine / Q000378:metabolism; D002882:Chromosomes, Human, Pair 13; D015672:Erythroid Precursor Cells / Q000378:metabolism*; D005260:Female; D005319:Fetal Hemoglobin / Q000378:metabolism; D005914:Globins / Q000096:biosynthesis*; D005998:Glycine / Q000378:metabolism; D006801:Humans; D007223:Infant; D008297:Male; D013577:Syndrome; D014314:Trisomy
D005914:Globins; D005319:Fetal Hemoglobin; D000409:Alanine; D005998:Glycine