Two homozygous mutations (R193W and 794/795 delAA) in the myophosphorylase gene in a patient with McArdle's disease.
We report two novel homozygous mutations in the myophosphorylase gene (PYGM) in a patient with McArdle's disease. A C-to-T transition that changed an arginine to tryptophan at codon 193 (R193W) in exon 5, and a deletion of two adenine base pairs in exon 20 at codon 794/795 (794/795 delAA) were identified. Several lines of evidence suggest the pathogenicity of both mutations: (i) they were the only nucleotide alteration in the coding region and adjacent exon/intron boundaries of the PYGM gene; (ii) the R193W mutation leads to the replacement of a highly conserved amino acid residue involved in glucose-6-P binding, and the 794/795 delAA mutation predicts a frameshift and premature termination of the protein; (iii) 60 normal controls and 20 disease controls did not have the mutations in their 160 alleles. Hum Mutat 15:294, 2000.
Martín
M A
MA
Centro de Investigación, Hospital Universitario 12 de Octubre, Madrid.
Rubio
J C
JC
Campos
Y
Y
Vílchez
J
J
Cabello
A
A
Arenas
J
J
D000293:Adolescent; D000595:Amino Acid Sequence; D001120:Arginine / Q000235:genetics; D001483:Base Sequence; D006012:Glycogen Storage Disease Type V / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D006005:Phosphorylases / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D014364:Tryptophan / Q000235:genetics
D014364:Tryptophan; D001120:Arginine; D006005:Phosphorylases