First-trimester prenatal diagnosis of Tay-Sachs disease.

The prenatal diagnosis of Tay-Sachs disease was made in two at-risk fetuses by the analysis of chorionic villi obtained at 9 and 11 menstrual weeks, respectively. The diagnoses were based on the absence of beta-hexosaminidase A activity as determined by: (1) specific enzyme assays, (2) anion-exchange chromatography, and (3) cellulose acetate gel electrophoresis. The enzymatic diagnoses were confirmed on fetal tissue as well as by ultrastructural demonstration of the first-trimester fetal neuropathology.

Glucose-6-phosphate dehydrogenase deficiency in Papua New Guinea. The description of 13 new variants.

A total of 362 males from various regions of Papua New Guinea were screened for red cell glucose-6-phosphate dehydrogenase (G6PD) activity. Twenty-six G6PD deficient individuals were identified. Biochemical characterization of G6PD purified from these subjects has revealed 13 new variants and several copies of previously described forms of G6PD.

Further evidence for heterogeneity of glucose-6-phosphate dehydrogenase deficiency in Papua New Guinea.

Four new G6PD variants have been characterized in individuals from Papua New Guinea. This study demonstrates that the previously reported Markham variant and the newly characterized Salata variant may be widely distributed in Papua New Guinea. Th data presented here together with those of previously published studies demonstrate a degree of heterogeneity of G6PD deficiency that is much higher than that in other regions of the world where G6PD deficiency is common.