Glucose-6 phosphate dehydrogenase deficiency: an easy and sensitive quantitative assay for the detection of female heterozygotes in red blood cells.

Different methods for the quantitative determination of glucose-6-phosphate dehydrogenase (G-6-PD) were compared and one of them found to be highly precise. Maleimide inactivation of 6-phosphogluconate dehydrogenase (PGD) was investigated. It was shown that this inactivation is time-dependent and causes loss of assay precision. The most precise method was adapted to lysates of red blood cells from females, known to be heterozygote for G-6-PD deficiency and from non-deficient males and females. Heterozygote gene carriers were detected at a rate of 97.0%.