A family with pseudodeficiency of acid alpha-glucosidase.
A unique family is presented which consists of a patient with the juvenile muscular dystrophy form of glycogenosis type II and four healthy individuals, both parents and sisters, with low acid alpha-glucosidase activity. It was almost impossible to distinguish the homozygote from the heterozygous members by lymphocyte assay alone. In cultured skin fibroblasts, acid alpha-glucosidase activity measured with a synthetic substrate was less than 1% of the normal mean value in the patient and about 15% in the parents. The activity toward glycogen was not detectable in the patient and was about 30% of the normal mean value in the parents. These values are also lower than expected in heterozygotes. To explain these results properly, a new mutant allele of acid alpha-glucosidase is proposed. Both parents could be compound heterozygotes for the pseudodeficiency allele and the juvenile form of glycogenosis type II allele.
Nishimoto
J
J
Department of Pediatrics, Osaka University Medical School, Japan.
Inui
K
K
Okada
S
S
Ishigami
W
W
Hirota
S
S
Yamano
T
T
Yabuuchi
H
H
D000293:Adolescent; D000328:Adult; D000483:Alleles; D005260:Female; D006008:Glycogen Storage Disease / Q000235:genetics*; D006009:Glycogen Storage Disease Type II / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D008297:Male; D009136:Muscular Dystrophies / Q000235:genetics*; D009154:Mutation; D010375:Pedigree; D012600:Scoliosis / Q000235:genetics; D000520:alpha-Glucosidases / Q000172:deficiency* / Q000235:genetics
D000520:alpha-Glucosidases