[The determination of amylo-1,6-glucosidase in biopsy specimens from human chorion]

This method has been developed for the prenatal diagnosis of a grave hereditary disease, a deficiency of amylo-1,6-glucosidase (A-1,6-G) activity. The methods suggested earlier did not rule out the effects of other glucosidases, that could result in false-positive data if the fetus was involved. The new method for measuring A-1,6-G activity includes sedimentation of acid alpha-glucosidase with rabbit blood antiserum to human placental acid alpha-glucosidase. A-1,6-G activity is estimated from the difference in glucose accrement with limit dextrin and glycogen used as substrates. A-1,6-G activities were measured in 15 chorion samples obtained in the first trimester of pregnancy by the developed method, and normal values of this parameter established, making up 39.77 +/- 8.1 nmol/h per g of protein. The method may be useful in the prenatal diagnosis of type III glycogenosis.