[Possible localization of the glutathione reductase (EC 1.6.4.2) on the 8p21 band]

Glutathione reductase (EC 1.6.4.2.) (GSR) activity was measured in the red cells of patients with different rearrangements of chromosome 8. Of three patients with mosaic trisomy 8, two had a high GSR activity. The lack of correlation between GSR levels and the degree of mosaicism in lymphocytes is discussed. In six patients with trisomy 8qter the mean value of GSR activities was normal. In one patient with trisomy pter leads to q22.1 and in two with trisomy p11 leads to p22, a significant increase (+60%) of GSR activity was observed. In two patients with monosomy p22 leads to pter and p21 leads to pter, respectively, the GSR levels were normal. It is concluded that the gene locus of GSR can be assigned to the 8p11 leads to p22 segment. A comparison of these results with one other case from the literature suggests a more precise assignment of the GSR locus to band p21.