Molecular characterization of McArdle's disease in two large Finnish families

We have studied two large unrelated Finnish families with myophosphorylase deficiency (McArdle's disease). In one, we identified a new nonsense mutation at codon 540 in exon 14 of the myophosphorylase gene, changing an encoded glutamic acid to a stop codon (E540X). The second family carried a splice-junction mutation at the 5' splice site of intron 14 (1844+G→A), previously reported in one Caucasian patient and in a consanguineous Druze family. These data further enlarge the list of mutations associated with McArdle's disease and establish that McArdle's disease is genetically heterogeneous also within the Finnish population. Copyright (C) 1999 Elsevier Science B.V.