Quantities of adult, fetal and embryonic globin chains in the blood of eighteen- to twenty-week-old human fetuses.
The prenatal diagnostic program, established at Hacettepe University in Ankara for the purpose of detecting beta-thalassemia (beta-thal), sickle cell anemia (SS), and Hb S-beta-thal, offered the opportunity of evaluating the relative quantities of adult (beta A, beta S), fetal (G gamma, A gamma, A gamma T), and embryonic (epsilon, zeta) chains in 26 fetuses, aged 18-20 weeks. Methodology involved micro high-performance liquid chromatographic (HPLC) procedures and immunology using an mAb, specific for the embryonic epsilon chain. A good correlation was observed between the beta/gamma in vitro chain synthesis ratio and the level of beta A and/or beta S chains determined by reversed-phase HPLC; the combination of these two sets of data strengthens the prenatal diagnostic approach of detecting beta-thal major but not beta-thal trait. The levels of the different gamma chains were about as observed in newborn babies; the frequency of the A gamma T variant in the 26 fetuses was the same as observed for a larger group of Turkish newborn babies. The level of the embryonic zeta chain was higher than seen in full-term babies and varied between 0 and 1.3%; 5 of the 26 fetuses showed the complete absence of zeta. The embryonic epsilon chain was not detectable, not even in babies with beta-thal major. These data indicate that the synthesis of epsilon is completely turned off in fetuses at the age of 18-20 weeks, while that of zeta continues, albeit at a low level.
Kutlar
F
F
Department of Cell and Molecular Biology, Medical College of Georgia, Augusta 30912-2100.
Moscoso
H
H
Kiefer
C R
CR
Garver
F A
FA
Beksaç
S
S
Onderoglu
L
L
Gurgey
A
A
Altay
C
C
Huisman
T H
TH
D000328:Adult; D000755:Anemia, Sickle Cell / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D004622:Embryo, Mammalian / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005333:Fetus / Q000378:metabolism*; D005865:Gestational Age; D005914:Globins / Q000032:analysis* / Q000172:deficiency / Q000276:immunology; D006441:Hemoglobin A / Q000032:analysis; D006801:Humans; D011247:Pregnancy; D013789:Thalassemia / Q000378:metabolism
D005914:Globins; D006441:Hemoglobin A