The autoantibody titer was calculated from the reduction in radioactivity, relative to that in a parallel response without serum extract. An ELISA was used to determine the existence of IgG bound to epitopes on purified folate receptors.6 In this assay, purified folate receptors from cow’s milk or human placental cells were immobilized in 96-well plates. Unbound sites had been blocked with rabbit serum. Nonspecific binding was motivated in laboratory control samples, and a worth of 2 SD above the mean was thought to represent nonspecific binding. This worth was subtracted from the values for all study samples. Assays for autoantibodies used cow’s-milk folate receptors because the antigen in Study 1 and human placental folate receptors as the antigen in Study 2.Having less a priming oligosaccharide chain clarifies the inability of glycogen synthase, which was present at regular levels in this affected person, to synthesize glycogen. Our finding of solely unglucosylated glycogenin-1 in the patient demonstrates the enzyme was defective; our molecular genetic data suggest that this was a rsulting consequence a missense mutation in one allele and a non-sense mutation without detectable expression in the additional. Autoglucosylation of glycogenin-1 occurs at Tyr195 by means of a glucose-1-O-tyrosine linkage.16 An induced missense mutation of this residue results in inactivated autoglucosylation.17,18 However, missense mutations affecting some other residues of glycogenin-1 have been proven to eliminate autoglucosylation also.