The prenatal diagnostic program, established at Hacettepe University in Ankara for the purpose of detecting β-thalassemia (β-thal), sickle cell anemia (SS), and Hb S-β-thal, offered the opportunity of evaluating the relative quantities of adult (βA, βS), fetal (Gγ, Aγ, AγT), and embryonic (ε, ζ) 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 ε chain. A good correlation was observed between the β γ in vitro chain synthesis ratio and the level of βA and/or βS chains determined by reversed-phase HPLC; the combination of these two sets of data strengthens the prenatal diagnostic approach of detecting β-thal major but not β-thal trait. The levels of the different γ chains were about as observed in newborn babies; the frequency of the AγT variant in the 26 fetuses was the same as observed for a larger group of Turkisch newborn babies. The level of the embryonic ζ 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 ζ. The embryonic ε chain was not detectable, not even in babies with β-thal major. These data indicate that the synthesis of ε is completely turned off in fetuses at the age of 18-20 weeks, while that of ζ continues, albeit at a low level.
|Original language||English (US)|
|Number of pages||10|
|Journal||Journal of Chromatography B: Biomedical Sciences and Applications|
|Publication status||Published - Jul 5 1991|
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