title: In search of non-random X inactivation: studies of fetal membranes heterozygous for glucose-6-phosphate dehydrogenase.
abstract: Extraembryonic membranes and fetal tissues were obtained from 55 specimens of 5--11 weeks conceptual age. The glucose-6-phosphate dehydrogenase (G6PD) electrophoretic phenotype was determined and correlated with that of maternal blood. Fifteen specimens were heterozygous for G6PD A, and for nine of these the maternal allele could be determined. In none of these specimens did the isozyme pattern of the membraneous chorion or chorionic villi differ significantly from that of fetal tissue. We have obtained no evidence of non-random inactivation in extraembryonic membranes of human fetal specimens at this stage of development.
mesh_terms: D005111:Extrachromosomal Inheritance; D005321:Extraembryonic Membranes / Q000201:enzymology*; D005260:Female; D014644:Genetic Variation; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007527:Isoenzymes / Q000235:genetics; D010641:Phenotype; D011247:Pregnancy; D012730:Sex Chromosomes; D014960:X Chromosome
chemical_list: D007527:Isoenzymes; D005954:Glucosephosphate Dehydrogenase