ACID ALPHA-GLUCOSIDASE DEFICIENCY - IDENTIFICATION AND EXPRESSION OF A MISSENSE MUTATION (S529V) IN A JAPANESE ADULT PHENOTYPE

We report a missense mutation in an adult Japanese patient with acid a lpha-glucosidase (GAA) deficiency, A TC to GT transition at nucleotide s 1585-1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V) in exon 11. We also have demon strated that the S529V mutation abolishes the catalytic activity of th e enzyme. Our data suggest that this mutation is the cause of the clin ical manifestation known as adult-onset GAA deficiency. The missense m utation described here is a new mutation, and the first identified in Japanese patients with GAA deficiency.