This variant, c.393del (p.Ser132fs), is a frameshift variant that is predicted to result in nonsense mediated decay and lack of gene product, meeting PVS1. The variant is absent in gnomAD v2.1.1, meeting PM2. To our knowledge, this variant has not been reported in the literature in individuals with Pompe disease, and results of experimental studies are not available. There is a ClinVar entry for this variant (Variation ID: 371580; 1 star review status) with 1 submitter classifying the variant as Likely Pathogenic. In summary, this variant meets the criteria to be classified as Likely Pathogenic for Pompe disease. GAA-specific ACMG/AMP criteria met, based on the specifications of the ClinGen LSD VCEP: PVS1, PM2.