Characterization of leukocyte glucose 6-phosphate dehydrogenase in Sardinian mutants.

Erythrocyte and Platelet Glucose 6‐Phosphate Dehydrogenase in Normal and Mutant Caucasians

“…In contrast, the platelet G6-PD pH optimum curve in the mutants, N.H. and M.H., was biphasic (Figures l b and lc). Similar biphasic pH optimum curves have been described in red cells of G6-PD-deficient Caucasian patients with detectable levels (Kirkman et al 1963) and in the leucocytes from Caucasian patients with severe G6-PD deficiencies (Bonsignore et al 1966). Electrophoresis of the enzyme from normal erythrocytes and platelets produced single bands with identical mobility and this was confirmed by mixing experiments.…”

“…The trays were then covered with glass slides and the samples run towards the anode for 4% hours with a current of 7 mA per strip. The electrophoresis procedure was carried out at 4" C. At the completion of the runs the gels were removed from the trays, sliced, and the lower portion of the gel was stained for G6-PD activity (Bonsignore et al 1966) or for 6-PGD activity or both. The staining procedure for 6-PGD was the same as for G6-PD except that glucose-6-phosphate was replaced by 6-phosphogluconate.…”

“…Thus it is likely that the very low activity of the mutant enzyme in erythrocytes is due to a combination of low specific activity (Bonsignore et al 1966) and increased susceptibility of the mutant enzyme to the erythrocyte intracellular environment.…”

“…Studies in subjects with inherited deficiency of erythrocyte glucose 6-phosphate dehydrogenase (G6-PD) have shown that in the Negro variant the deficiency is mainly confined to erythrocytes , while in Caucasian mutants with severe erythrocyte enzyme deficiency other tissues, including leucocytes , platelets (Ramot et al 1959), saliva (Ramot et al 1960), liver , skin (Gartler et al 1962), kidney and adrenals (Chan et al 1965) are involved. The electrophoretic mobility of G6-PD in leucocytes from patients with severe red cell deficiency has been reported to be slower than normal in Italians (Bonsignore et al 1966) and to be of normal mobility in Sephardic Jews (Ramot et al 1964, Justice The activity, pH optimum and electrophoretic mobility of platelet glucose-6-phosphate dehydrogenase (G6-PD) was investigated in subjects with severe Mediterranean type G6-PD deficiency. Enzyme activity was less than 1 % of normal in erythrocytes and 20.…”

Glucose‐6‐phosphate dehydrogenase deficiency in Sicily. Incidence, biochemical characteristics and clinical implications

“…This enzymatic deficiency is present in the leukocytes, platelets and saliva, as found in Caucasian people (Ramot et al 1959, Marks & Gross 1959, Bonsignore et al 1966, Justice et al 1966, Russo et al 1969.…”