A homozygous missense mutation (A659D) in the myophosphorylase gene in a Spanish patient with McArdle's disease

We identified a novel missense mutation in the myophosphorylase gene (PYGM) in a Spanish patient with McArdle's disease. This homozygous C-to-A mutati on results in the replacement of a highly conserved alanine at amino acid p osition 659 with an aspartic acid in the C-terminal domain of the myophosph orylase gene protein, near binding sites for pyridoxal phosphate and glucos e. Our data further expand the genetic heterogeneity in patients with McArd le's disease. (C) 2000 Elsevier Science B.V. All rights reserved.