PRENATAL ANALYSIS IN 2 SUSPECTED CASES OF GLUTATHIONE SYNTHETASE DEFICIENCY

Prenatal diagnosis was performed in a family affected by generalized g lutathione synthetase deficiency. The disorder is transmitted by autos omal recessive inheritance. The first child born in this family died o f the disorder at 6 weeks of age. Prenatal diagnosis was performed in two subsequent pregnancies. Amniotic fluid samples were collected by a mniocentesis in the 16th and 17th weeks of pregnancy, respectively. In the case of the second pregnancy the concentration of 5-oxoproline in the amniotic fluid was measured by stable isotope dilution, while bot h stable isotope dilution and glutathione synthetase activity measurem ents were employed in the prenatal analysis of the third pregnancy. Th e 5-oxoproline concentration in the second pregnancy was even lower th an that of the controls and in the case of the third pregnancy the res ults fell within the control range. The second pregnancy resulted in t he birth of a clinically healthy girl, and the outcome of 5-oxoproline concentration in a urine sample taken just after birth confirmed the unaffected state. The third pregnancy resulted in the birth of a healt hy boy at term, and the 5-oxoproline concentration in his urine and th e glutathione synthetase activity in haemolysates were determined. The results confirmed that this infant was also unaffected and he apparen tly had two normal alleles for the enzyme.