Fig. 1

Sequence analysis of exon 5 of the GAA gene. Both parents are heterozygous for c.921A > T, a silent change (p.Ala307 = ), the proband shows a homozygous T pattern. Position 925 is indicated by arrows. The father is heterozygous for c.925G > A; p.(Gly309Arg), a known pathogenic variant, mother has wild type sequence. The proband shows skewed, pseudoheterozygous, patterns in leukocytes and (briefly) cultured fibroblasts, with the highest mutant peak in the fibroblasts