California G GAA sequencing Pompe disease Pompe disease diagnostics testing Technology: general issues acid α-glucosidase alpha glucosidase c.-32-13T&amp cross-reactive immunologic material diagnosis dried blood spots enzyme replacement therapy follow-up genotype-phenotype correlation gt immune modulation therapy infantile onset Pompe disease infantile-onset infantile-onset Pompe disease late onset Pompe disease late-onset lysosomal storage diseases new disorders implementation newborn screening next generation sequencing patient perspective presymptomatic pseudodeficiency treatment and follow-up