The NM_000152.5:c.2242del (p.Glu748ArgfsTer16) variant in GAA is a frameshift variant predicted to cause a premature stop codon in biologically-relevant-exon 16/20, leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1). This variant is absent in gnomAD v2.1.1 (PM2_Supporting). To our knowledge, this variant has not been reported in the literature in patients with Pompe disease. There is a ClinVar entry for this variant (Variation ID 370639; 1 star review status) with one submitter classifying the variant as likely pathogenic. This variant meets the criteria to be classified as Likely Pathogenic for Pompe disease based on the recommendations of the ClinGen Sequence Variant Interpretation Working Group (https://clinicalgenome.org/site/assets/files/5182/pm2_-_svi_recommendation_-_approved_sept2020.pdf). ACMG/AMP criteria met, as specified by the ClinGen Lysosomal Storage Disorders Expert Panel (Specification Version 2.0): PVS1, PM2_Supporting