GAA and methylmalonic acidemia: From April 2013 to November 2016, 103, 204 newborns were screened, 71 had low acid alpha‐glucosidase (AαGlu) activity and led to identification of only four pathogenic variants in the screening cohort.19 In another study from China, 236, 368 newborns were screened for methylmalonic acidemia (MMA).