Double trouble: combined myophosphorylase and AMP deaminase deficiency in a child homozygous for nonsense mutations at both loci.
A 2-yr-old boy had congenital hypotonia, limb weakness, exercise intolerance and one episode of myoglobinuria. Histochemical and biochemical analysis of muscle showed a combined defect of phosphorylase and AMP deaminase. DNA analysis showed that the child was homozygous for the mutations commonly found in both McArdle's disease and AMP deaminase deficiency. The father was heterozygous for both mutations. The mother was heterozygous for the myophosphorylase gene mutation and homozygous for the mutation in the AMP deaminase 1 gene.
Tsujino
S
S
H. Houston Merritt Clinical Research Center for Muscular Dystrophy and Related Disease, Department of Neurology, Columbia-Presbyterian Medical Center, New York 10032, USA.
Shanske
S
S
Carroll
J E
JE
Sabina
R L
RL
DiMauro
S
S
D000659:AMP Deaminase / Q000172:deficiency* / Q000235:genetics; D001483:Base Sequence; D002675:Child, Preschool; D018389:Codon, Nonsense / Q000378:metabolism*; D005260:Female; D006720:Homozygote; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000502:physiology; D010375:Pedigree; D010641:Phenotype; D006005:Phosphorylases / Q000172:deficiency* / Q000235:genetics
D018389:Codon, Nonsense; D006005:Phosphorylases; D000659:AMP Deaminase