Detection of the Sickle Gene in the Human Fetus

Abstract
A method for detection of the types of globin chains synthesized by first-trimester fetuses has been established with umbilical-cord blood derived from fetuses removed at hysterotomy. The blood is incubated with radioactive leucine, and the globin chains chromatographed on carboxymethyl cellulose in the presence of 8 M urea. The presence of beta A or beta S chains is verified by subsequent co-chromatography, digestion with trypsin and high-voltage electrophoresis. Since maternal blood makes an unimportant contribution to the radioactivity observed in fetal radiochromatograms, mixed placental blood provides an adequate sample for the detection of globin-chain synthesis by the fetus. Thus, if mixed placental blood is aspirated, sickle-cell trait in a fetus can be detected. This method provides an approach to focused genetic counseling for disorders of hemoglobin.